AS FILED WITH THE SECURITIES AND EXCHANGE COMMISSION ON OCTOBER 25, 2005

1933 Act File No. 333-114111
1940 Act File No. 811-21547


U.S. SECURITIES AND EXCHANGE COMMISSION
WASHINGTON, D.C. 20549
FORM N-2

(CHECK APPROPRIATE BOXES)

[ ] REGISTRATION STATEMENT UNDER THE SECURITIES ACT OF 1933

[X] PRE-EFFECTIVE AMENDMENT NO. 4

[ ] POST-EFFECTIVE AMENDMENT NO.
and/or
[ ] REGISTRATION STATEMENT UNDER THE INVESTMENT COMPANY ACT OF 1940

[X] AMENDMENT NO. 6

CALAMOS GLOBAL TOTAL RETURN FUND
Exact Name of Registrant as Specified in Charter

2020 Calamos Court, Naperville, Illinois 60563
Address of Principal Executive Offices (Number, Street, City, State, Zip Code)

(630) 245-7200
Registrant's Telephone Number, including Area Code

James S. Hamman, Jr.
Executive Vice President
Calamos Advisors LLC
2020 Calamos Court
Naperville, Illinois 60563

Name and Address (Number, Street, City, State, Zip Code) of Agent for Service

COPIES OF COMMUNICATIONS TO:

     David A. Sturms                  Cameron S. Avery                  Cynthia G. Cobden
Vedder, Price, Kaufman &           Bell, Boyd & Lloyd, LLC       Simpson Thacher & Bartlett LLP
     Kammholz, P.C.                70 West Madison Street             425 Lexington Avenue
    222 North LaSalle                    Suite 3300                    New York, NY 10017
    Chicago, IL 60601              Chicago, IL 60602-4207

APPROXIMATE DATE OF PROPOSED PUBLIC OFFERING: As soon as practicable after the
effective date of this Registration Statement

If any of the securities being registered on this Form will be offered on a delayed or continuous basis in reliance on Rule 415 under the Securities Act of 1933, as amended (the "Securities Act"), other than securities offered in connection with a dividend or interest reinvestment plans, check the following box. [ ]

It is proposed that this filing will become effective (check appropriate box)

[ ] when declared effective pursuant to section 8(c).

CALCULATION OF REGISTRATION FEE UNDER THE SECURITIES ACT OF 1933

-----------------------------------------------------------------------------------------------------------------------------
-----------------------------------------------------------------------------------------------------------------------------
                                                                                PROPOSED MAXIMUM
    TITLE OF SECURITIES              AMOUNT            PROPOSED MAXIMUM        AGGREGATE OFFERING            AMOUNT OF
      BEING REGISTERED          BEING REGISTERED    OFFERING PRICE PER UNIT         PRICE(1)            REGISTRATION FEE(2)
-----------------------------------------------------------------------------------------------------------------------------
Common Shares (no par value)       7,666,667                $15.00                $115,000,005              $13,535.50
-----------------------------------------------------------------------------------------------------------------------------
-----------------------------------------------------------------------------------------------------------------------------

(1) Estimated solely for the purpose of calculating the registration fee.

(2) $13,535.50 was previously paid.

THE REGISTRANT HEREBY AMENDS THIS REGISTRATION STATEMENT ON SUCH DATE OR DATES AS MAY BE NECESSARY TO DELAY ITS EFFECTIVE DATE UNTIL THE REGISTRANT SHALL FILE A FURTHER AMENDMENT, WHICH SPECIFICALLY STATES THIS REGISTRATION STATEMENT SHALL THEREAFTER BECOME EFFECTIVE IN ACCORDANCE WITH SECTION 8(a) OF THE SECURITIES ACT OR UNTIL THE REGISTRATION STATEMENT SHALL BECOME EFFECTIVE ON SUCH DATE AS THE COMMISSION, ACTING PURSUANT TO SAID SECTION 8(a), MAY DETERMINE.



THE INFORMATION IN THIS PROSPECTUS IS NOT COMPLETE AND MAY BE CHANGED. WE MAY NOT SELL THESE SECURITIES UNTIL THE REGISTRATION STATEMENT FILED WITH THE SECURITIES AND EXCHANGE COMMISSION IS EFFECTIVE. THIS PROSPECTUS IS NOT AN OFFER TO SELL THESE SECURITIES AND IT IS NOT SOLICITING AN OFFER TO BUY THESE SECURITIES IN ANY STATE WHERE THE OFFER OR SALE IS NOT PERMITTED.

SUBJECT TO COMPLETION, DATED OCTOBER 25, 2005

PROSPECTUS

4,000,000 SHARES

CALAMOS GLOBAL TOTAL RETURN FUND
COMMON SHARES OF BENEFICIAL INTEREST
$15.00 PER SHARE

Investment Objective. Calamos Global Total Return Fund (the "Fund") is a newly organized, diversified, closed-end management investment company. The Fund's investment objective is to provide total return through a combination of capital appreciation and current income.

Portfolio Contents. Under normal circumstances, the Fund will invest primarily in a portfolio of common and preferred stocks, convertible securities and income producing securities such as investment grade and below investment grade (high yield/high risk) debt securities. The Fund, under normal circumstances, will invest at least 50% of its managed assets in equity securities (including securities that are convertible into equity securities). The Fund may invest up to 100% of its managed assets in securities of foreign issuers, including debt and equity securities of corporate issuers and debt securities of government issuers, in developed and emerging markets. Under normal circumstances, the Fund will invest at least 30% of its managed assets in securities of foreign issuers. The Fund will invest in the securities of issuers of several different countries throughout the world, in addition to the United States. The Fund may also seek to generate income from option premiums by writing (selling) options (with an aggregate notional value of up to 33% of the value of the Fund's managed assets). "Managed assets" means the total assets of the Fund (including any assets attributable to any leverage that may be outstanding) minus the sum of accrued liabilities (other than debt representing financial leverage). For this purpose the liquidation preference on any preferred shares will not constitute a liability. Below investment grade (high yield/high risk) securities are rated Ba or lower by Moody's Investors Service, Inc. ("Moody's") or BB or lower by Standard & Poor's, a division of The McGraw-Hill Companies, Inc. ("Standard & Poor's") or are unrated securities of comparable quality as determined by the Fund's investment adviser. Below investment grade securities are commonly referred to as "junk bonds" and are considered speculative with respect to the issuer's capacity to pay interest and repay principal. They involve greater risk of loss, are subject to greater price volatility and are less liquid, especially during periods of economic uncertainty or change, than higher rated securities. There can be no assurance that the Fund will achieve its investment objective.

NO PRIOR HISTORY. BECAUSE THE FUND IS NEWLY ORGANIZED, ITS COMMON SHARES HAVE NO HISTORY OF PUBLIC TRADING. SHARES OF CLOSED-END FUNDS FREQUENTLY TRADE AT A DISCOUNT FROM THEIR NET ASSET VALUE. THE RISK OF LOSS DUE TO A MARKET DISCOUNT MAY BE GREATER FOR INITIAL INVESTORS EXPECTING TO SELL THEIR SHARES IN A RELATIVELY SHORT PERIOD AFTER COMPLETION OF THE PUBLIC OFFERING. The common shares have been approved for listing on the New York Stock Exchange under the symbol "CGO."

(continued on following page)

INVESTING IN THE FUND'S COMMON SHARES INVOLVES RISKS. SEE "RISK FACTORS"

BEGINNING ON PAGE 28.

Neither the Securities and Exchange Commission nor any state securities commission has approved or disapproved of these securities or determined if this prospectus is truthful or complete. Any representation to the contrary is a criminal offense.

                                                              PER SHARE         TOTAL(3)
                                                              ---------         ---------
Public offering price                                          $15.000          $
Sales load(1)                                                  $ 0.675          $
Estimated offering expenses                                    $ 0.030          $
Proceeds, after expenses, to the Fund(2)                       $14.295          $

(1) Calamos Advisors LLC ("Calamos"), the Fund's investment adviser (not the Fund), will pay certain additional compensation to Citigroup Global Markets Inc. and UBS Securities LLC. See "Underwriting." The total compensation received by the underwriters will not exceed 9.0% of the aggregate initial public offering price of the common shares offered hereby.

(2) Total organizational expenses and offering costs (other than the sales load, but including reimbursement of underwriter expenses of $0.005 per share) are estimated to be $ or $ per share. Calamos has agreed to pay organizational expenses and offering costs of the Fund (other than sales load, but including reimbursement of underwriter expenses of $0.005 per share) that exceed $0.03 per share.

(3) The Fund has granted the underwriters an option to purchase up to an additional common shares at the public offering price less the sales load within 45 days from the date of this prospectus, solely to cover overallotments, if any. If such option is exercised in full, the total public offering price, sales load, estimated offering expenses and proceeds, after expenses, to the Fund will be $ , $ , $ and $ , respectively. See "Underwriting."

The underwriters expect to deliver the common shares to purchasers on or about , 2005.

CITIGROUP                                              UBS INVESTMENT BANK
ADVEST, INC.                                          ROBERT W. BAIRD & CO.
H&R BLOCK FINANCIAL ADVISORS, INC.                     FERRIS, BAKER WATTS
                                                           INCORPORATED
JANNEY MONTGOMERY SCOTT LLC                           LEGG MASON WOOD WALKER
                                                           INCORPORATED
RBC CAPITAL MARKETS                                 STIFEL, NICOLAUS & COMPANY
                                                           INCORPORATED

WEDBUSH MORGAN SECURITIES INC.

, 2005


(continued from previous page)

Investment Adviser. Calamos is the Fund's investment adviser. See "Management of the Fund."

Leverage. The Fund may, but is not required to, issue preferred shares, borrow money or issue debt securities. These practices are known as leverage. The Fund currently anticipates that it will issue cumulative preferred shares, as soon as practicable after the closing of this offering, with an aggregate liquidation preference of up to approximately 33% of the Fund's total assets immediately after issuance. As a non-fundamental policy, such preferred shares, borrowings or debt securities may not exceed 38% of the Fund's total assets. The Fund may not be leveraged at all times and the amount of borrowings or leverage, if any, may vary depending upon a variety of factors, including Calamos' outlook for the market and the costs that the Fund would incur as a result of such leverage. The use of preferred shares, borrowings or debt securities to leverage the common shares creates risks. See "Risk Factors -- Leverage" beginning on page 32 of this prospectus.

You should read this prospectus, which contains important information about the Fund, before deciding whether to invest in the Fund's common shares, and retain it for future reference. A statement of additional information, dated , 2005, containing additional information about the Fund, has been filed with the Securities and Exchange Commission (the "Commission") and is incorporated by reference in its entirety into this prospectus. You may request a free copy of the statement of additional information, the table of contents of which is on page 52 of this prospectus, or the Fund's annual and semi-annual report by calling 1-800-582-6959 or by writing to the Fund. The Fund's annual and semi-annual reports are also available on its website at www.calamos.com, which will also provide a link to the Commission's website where the Fund's Statement of Additional Information may be obtained, as described below. You can review and copy documents the Fund has filed at the Commission's Public Reference Room in Washington, D.C. Call 1-202-551-8090 for information. The Commission charges a fee for copies. You can get the same information free from the Commission's EDGAR database on the Internet (http://www.sec.gov). You may also e-mail requests for these documents to publicinfo@sec.gov or make a request in writing to the Commission's Public Reference Section, Washington, D.C. 20549-0213.

The Fund's common shares do not represent a deposit or obligation of, and are not guaranteed or endorsed by, any bank or other insured depository institution and are not federally insured by the Federal Deposit Insurance Corporation, the Federal Reserve Board or any other government agency.


YOU SHOULD RELY ONLY ON THE INFORMATION CONTAINED IN OR INCORPORATED BY REFERENCE IN THIS PROSPECTUS. WE HAVE NOT, AND THE UNDERWRITERS HAVE NOT, AUTHORIZED ANY OTHER PERSON TO PROVIDE YOU WITH DIFFERENT INFORMATION. IF ANYONE PROVIDES YOU WITH DIFFERENT OR INCONSISTENT INFORMATION, YOU SHOULD NOT RELY ON IT. WE ARE NOT, AND THE UNDERWRITERS ARE NOT, MAKING AN OFFER TO SELL THESE SECURITIES IN ANY JURISDICTION WHERE THE OFFER OR SALE IS NOT PERMITTED.


TABLE OF CONTENTS

                                                              PAGE
                                                              ----
Prospectus Summary..........................................    1
Summary of Fund Expenses....................................   16
The Fund....................................................   17
Use of Proceeds.............................................   17
Investment Objective and Principal Investment Strategies....   18
Leverage....................................................   24
Interest Rate Transactions..................................   26
Risk Factors................................................   28
Management of the Fund......................................   35
Dividends and Distributions; Automatic Dividend Reinvestment
  Plan......................................................   37
Closed-End Fund Structure...................................   41
U.S. Federal Income Tax Matters.............................   41
Net Asset Value.............................................   44
Description of Shares.......................................   45
Certain Provisions of the Agreement and Declaration of Trust
  and By-Laws...............................................   46
Underwriting................................................   49
Custodian, Transfer Agent and Dividend Disbursing Agent.....   51
Legal Opinions..............................................   51
Table of Contents of The Statement of Additional
  Information...............................................   52

i

PROSPECTUS SUMMARY

This is only a summary. This summary does not contain all of the information that you should consider before investing in the Fund's common shares. You should review the more detailed information contained in this prospectus and in the statement of additional information, especially the information set forth under the heading "Risk Factors."

THE FUND......................   Calamos Global Total Return Fund is a newly
                                 organized, diversified, closed-end management
                                 investment company. Throughout the prospectus,
                                 we refer to Calamos Global Total Return Fund as
                                 the "Fund" or as "we," "us," or "our." See "The
                                 Fund."

THE OFFERING..................   The Fund is offering common shares of
                                 beneficial interest ("common shares") at an
                                 initial offering price of $15.00 per share. The
                                 common shares are being offered by a group of
                                 underwriters led by Citigroup Global Markets
                                 Inc., UBS Securities LLC, Advest, Inc., Robert
                                 W. Baird & Co. Incorporated, H&R Block
                                 Financial Advisors, Inc., Ferris, Baker Watts,
                                 Incorporated, Janney Montgomery Scott LLC, Legg
                                 Mason Wood Walker, Incorporated, RBC Capital
                                 Markets Corporation, Stifel, Nicolaus &
                                 Company, Incorporated and Wedbush Morgan
                                 Securities Inc. You must purchase at least 100
                                 common shares ($1,500) in order to participate
                                 in the offering. The Fund has granted the
                                 underwriters the right to purchase up to an
                                 additional           common shares at the
                                 public offering price, less the sales load,
                                 within 45 days from the date of this prospectus
                                 to cover overallotments. Calamos has agreed to
                                 pay organizational expenses and offering costs
                                 (other than sales load, but including
                                 reimbursement of underwriter expenses of $0.005
                                 per share) that exceed $0.03 per share. See
                                 "Underwriting."

INVESTMENT OBJECTIVE..........   The Fund's investment objective is to provide
                                 total return through a combination of capital
                                 appreciation and current income. There can be
                                 no assurance that the Fund will achieve its
                                 investment objective. See "Investment Objective
                                 and Principal Investment
                                 Strategies -- Investment Objective."

INVESTMENT POLICIES...........   Principal Investments.  Under normal
                                 circumstances, the Fund will invest primarily
                                 in a portfolio of common and preferred stocks,
                                 convertible securities and income producing
                                 securities such as investment grade and below
                                 investment grade (high yield/high risk) debt
                                 securities. The Fund, under normal
                                 circumstances, will invest at least 50% of its
                                 managed assets in equity securities (including
                                 securities that are convertible into equity
                                 securities). The Fund may invest up to 100% of
                                 its managed assets in securities of foreign
                                 issuers, including debt and equity securities
                                 of corporate issuers and debt securities of
                                 government issuers, in developed and emerging
                                 markets. Under normal circumstances, the Fund
                                 will invest at least 30% of its managed assets
                                 in securities of foreign issuers. The Fund will
                                 invest in the securities of issuers of several
                                 different countries throughout the world, in
                                 addition to the United States.

                                 Calamos will dynamically allocate the Fund's
                                 investments among multiple asset classes
                                 (rather than maintaining a fixed or static

                                        1

                                 allocation), seeking to obtain an appropriate
                                 balance of risk and reward through all market
                                 cycles using multiple strategies and combining
                                 them to seek to achieve favorable risk adjusted
                                 returns. See "Investment Objective and
                                 Principal Investment Strategies -- Principal
                                 Investment Strategies."

                                 The Fund will attempt to keep a consistent
                                 balance between risk and reward over the course
                                 of different market cycles, through various
                                 combinations of stocks, bonds, and/or
                                 convertible securities, to achieve what Calamos
                                 believes to be an appropriate blend for the
                                 then current market. As the market environment
                                 changes, portfolio securities may change in an
                                 attempt to achieve a relatively consistent risk
                                 level over time. At some points in a market
                                 cycle, one type of security may make up a
                                 substantial portion of the Fund's portfolio,
                                 while at other times certain securities may
                                 have minimal or no representation, depending on
                                 market conditions. See "Investment Objective
                                 and Principal Investment
                                 Strategies -- Principal Investment Strategies."

                                 The Fund may also seek to generate income from
                                 option premiums by writing (selling) options
                                 (with an aggregate notional value of up to 33%
                                 of the value of the Fund's managed assets). The
                                 Fund will opportunistically employ a strategy
                                 of writing options. The extent of option
                                 writing activity will depend upon market
                                 conditions and Calamos' ongoing assessment of
                                 the attractiveness of writing options on the
                                 Fund's equity holdings. See "Investment
                                 Objective and Principal Investment
                                 Strategies -- Principal Investment Strategies."

                                 Equity Securities.  Equity securities include
                                 common and preferred stocks, warrants, rights,
                                 and depository receipts. Under normal
                                 circumstances, the Fund will invest at least
                                 50% of its managed assets in equity securities
                                 (including securities that are convertible into
                                 equity securities). The Fund may invest in
                                 preferred stocks and convertible securities of
                                 any rating, including below investment grade.

See "-- High Yield Securities" below. An investment in the equity securities of a company represents a proportionate ownership interest in that company. Therefore, the Fund participates in the financial success or failure of any company in which it has an equity interest.

High Yield Securities. The Fund may invest in high yield securities for either current income or capital appreciation or both. These securities are rated below investment grade (i.e., rated Ba or lower by Moody's or BB or lower by Standard & Poor's) or are unrated securities of comparable quality as determined by Calamos, the Fund's investment adviser. The Fund expects that it initially will invest approximately 30% of its managed assets in high yield securities, which percentage may change over time. The Fund may invest in high yield securities of any rating. Non-convertible debt securities rated below investment grade are commonly referred to as "junk bonds" and are considered speculative with respect to the issuer's capacity to pay interest and repay principal. They involve greater risk of loss, are subject to greater price volatility and are less liquid, especially during

2

periods of economic uncertainty or change, than higher rated debt securities.

Foreign Securities. The Fund may invest up to 100% of its managed assets in securities of foreign issuers, including debt and equity securities of corporate issuers and debt securities of government issuers, in developed and emerging markets. The Fund expects that it initially will invest more than 50% of its managed assets in securities of foreign issuers, which percentage may change over time, depending on Calamos' ongoing assessment of market opportunities for the Fund. Under normal circumstances, the Fund will invest at least 30% of its managed assets in securities of foreign issuers. The Fund will invest in the securities of issuers of several different countries throughout the world, in addition to the United States. A foreign issuer is a company organized under the laws of a foreign country.

Convertible Securities. The Fund may invest in convertible securities. A convertible security is a debt security or preferred stock that is exchangeable for an equity security (typically of the same issuer) at a predetermined price (the "conversion price") or a security that mandatorily converts to an equity security at a predetermined time. Depending upon the relationship of the conversion price to the market value of the underlying security, a convertible security may trade more like an equity security than a debt instrument. The Fund may invest in convertible securities of any rating. Securities that are convertible into equity securities are considered equity securities for purposes of the Fund's policy to invest at least 50% of its managed assets in equity securities. See "Investment Objective and Principal Investment Strategies -- Principal Investment Strategies -- Convertible Securities."

Synthetic Convertible Instruments. Calamos may also establish a "synthetic" convertible instrument by combining separate securities that possess economic characteristics similar to a convertible security, i.e., an income component and the right or obligation to convert to an equity security ("convertible component"). The income component is achieved by investing in non-convertible, fixed-income securities such as bonds, preferred stocks, money market instruments and other instruments that provide an income component. The convertible component is achieved by investing in warrants or options to buy common stock at a certain exercise price, or options on a stock index. The Fund may also purchase synthetic convertible instruments created by other parties, typically investment banks, including convertible structured notes. Different companies may issue the income and convertible components, which may be purchased separately, and at different times. The Fund's holdings of synthetic convertible instruments are considered equity securities for purposes of the Fund's policy to invest at least 50% of its managed assets in equity securities. If the Fund purchases a synthetic convertible instrument, a component of which is an option, such option will not be considered an option for the purpose of the Fund's limitations on options described below. See "Investment Objective and Principal Investment Strategies --

3

Principal Investment Strategies -- Synthetic Convertible Instruments."

Options. The Fund may also seek to generate income from option premiums by writing (selling) options (with an aggregate notional value of up to 33% of the value of the Fund's managed assets). The Fund may write (sell) call options (i) on a portion of the equity securities (including securities that are convertible into equity securities) in the Fund's portfolio and (ii) on broad-based securities indices (such as the S&P 500 or MSCI EAFE) or certain ETFs (exchange traded funds) that trade like common stocks but seek to replicate such market indices. See "Investment Objective and Principal Investment Strategies -- Principal Investment Strategies -- Options."

Rule 144A Securities. The Fund may invest without limit in securities that have not been registered for public sale, but that are eligible for purchase and sale by certain qualified institutional buyers ("Rule 144A Securities"). Calamos, under the supervision of the Board of Trustees, will determine whether Rule 144A Securities are illiquid (that is, not readily marketable) and thus subject to the Fund's limit on investing no more than 15% of its managed assets in illiquid securities. See "Investment Objective and Principal Investment Strategies -- Principal Investment Strategies -- Rule 144A Securities."

Zero Coupon Securities. The securities in which the Fund invests may include zero coupon securities, which are debt obligations that are issued or purchased at a significant discount from face value. The discount approximates the total amount of interest the security will accrue and compound over the period until maturity or the particular interest payment date at a rate of interest reflecting the market rate of the security at the time of issuance. Zero coupon securities do not require the periodic payment of interest. These investments benefit the issuer by mitigating its need for cash to meet debt service, but generally require a higher rate of return to attract investors who are willing to defer receipt of cash. These investments may experience greater volatility in market value than U.S. government or other securities that make regular payments of interest. The Fund accrues income on these investments for tax and accounting purposes, which is distributable to shareholders and which, because no cash is received at the time of accrual, may require the liquidation of other portfolio securities to satisfy the Fund's distribution obligations, in which case the Fund will forego the opportunity to purchase additional income producing assets with the liquidation proceeds. Zero coupon U.S. government securities include STRIPS and CUBES, which are issued by the U.S. Treasury as component parts of U.S. Treasury bonds and represent scheduled interest and principal payments on the bonds.

Other Securities. The Fund may invest in other securities of various types. Normally, the Fund invests substantially all of its assets to meet its investment objective. For temporary defensive purposes, the Fund may depart from its principal investment

4

                                 strategies and invest part or all of its assets
                                 in securities with remaining maturities of less
                                 than one year, cash equivalents, or may hold
                                 cash. During such periods, the Fund may not be
                                 able to achieve its investment objective. See
                                 "Investment Objective and Principal Investment
                                 Strategies -- Principal Investment Strategies."

USE OF LEVERAGE BY THE FUND...   The Fund may, but is not required to, use
                                 leverage by issuing preferred shares, borrowing
                                 money or issuing debt securities. The Fund
                                 currently anticipates that it will issue
                                 cumulative preferred shares, as soon as
                                 practicable after the closing of this offering,
                                 with an aggregate liquidation preference of up
                                 to approximately 33% of the Fund's total
                                 assets. As a non-fundamental policy, such
                                 preferred shares, borrowings or debt securities
                                 may not exceed 38% of the Fund's total assets.
                                 However, the Board of Trustees reserves the
                                 right to issue preferred shares or debt
                                 securities or borrow to the extent permitted by
                                 the Investment Company Act of 1940 (the "1940
                                 Act"). See "Leverage." The Fund may not be
                                 leveraged at all times and the amount of
                                 borrowing or leverage, if any, may vary
                                 depending upon a variety of factors, including
                                 Calamos' outlook for the market and the costs
                                 that the Fund would incur as a result of such
                                 leverage. Leverage involves greater risks. The
                                 Fund's leveraging strategy may not be
                                 successful. By leveraging its investment
                                 portfolio, the Fund creates an opportunity for
                                 increased net income or capital appreciation.
                                 However, the use of leverage also involves
                                 risks, which can be significant. These risks
                                 include the possibility that the value of the
                                 assets acquired with the proceeds of leverage
                                 decreases although the Fund's liability to
                                 holders of preferred shares or other types of
                                 leverage is fixed, greater volatility in the
                                 Fund's net asset value and the market price of
                                 the Fund's common shares and higher expenses.
                                 In addition, the rights of lenders and the
                                 holders of preferred shares and debt securities
                                 issued by the Fund will be senior to the rights
                                 of the holders of common shares with respect to
                                 the payment of dividends or upon liquidation.
                                 Holders of preferred shares will have voting
                                 rights in addition to and separate from the
                                 voting rights of common shareholders. See
                                 "Description of Shares -- Preferred Shares" and
                                 "Certain Provisions of the Agreement and
                                 Declaration of Trust and By-Laws." The holders
                                 of preferred shares, on the one hand, and the
                                 holders of the common shares, on the other, may
                                 have interests that conflict in certain
                                 situations. Since Calamos' management fee is
                                 based upon a percentage of the Fund's managed
                                 assets, which include assets attributable to
                                 any outstanding leverage, the investment
                                 management fee (which is effectively borne by
                                 common shareholders and not holders of the
                                 Fund's leverage) will be higher if the Fund is
                                 leveraged and Calamos will have an incentive to
                                 leverage the Fund. Calamos intends to leverage
                                 the Fund only when it believes that the
                                 potential return on additional investments
                                 acquired with the proceeds of leverage is
                                 likely to exceed the costs incurred in
                                 connection with the borrowing or issuance and
                                 ongoing maintenance of preferred shares or debt
                                 securities. The Fund will pay, and common
                                 shareholders will effectively bear, any costs
                                 and expenses relating to any borrowings and to
                                 the issuance and

                                        5

                                 ongoing maintenance of preferred shares or debt
                                 securities. Such costs and expenses include the
                                 higher management fee resulting from the use of
                                 any such leverage. See "Leverage" and "Risk
                                 Factors -- Leverage."

INTEREST RATE TRANSACTIONS....   In order to seek to reduce the interest rate
                                 risk inherent in the Fund's underlying
                                 investments and capital structure, the Fund, if
                                 market conditions are deemed favorable, may
                                 enter into interest rate swap or cap
                                 transactions to attempt to protect itself from
                                 increasing dividend or interest expenses on its
                                 leverage. The use of interest rate swaps and
                                 caps is a highly specialized activity that
                                 involves investment techniques and risks
                                 different from those associated with ordinary
                                 portfolio security transactions.

                                 In an interest rate swap, the Fund would agree
                                 to pay to the other party to the interest rate
                                 swap (which is known as the "counterparty") a
                                 fixed rate payment in exchange for the
                                 counterparty agreeing to pay to the Fund a
                                 payment at a variable rate that is expected to
                                 approximate the rate on any variable rate
                                 payment obligation on the Fund's leverage. The
                                 payment obligations would be based on the
                                 notional amount of the swap.

                                 In an interest rate cap, the Fund would pay a
                                 premium to the counterparty to the interest
                                 rate cap and, to the extent that a specified
                                 variable rate index exceeds a predetermined
                                 fixed rate, would receive from the counterparty
                                 payments of the difference based on the
                                 notional amount of such cap. Depending on the
                                 state of interest rates in general, the Fund's
                                 use of interest rate swap or cap transactions
                                 could enhance or harm the overall performance
                                 of the common shares. See "Interest Rate
                                 Transactions."

INVESTMENT ADVISER............   Calamos is the Fund's investment adviser.
                                 Calamos is responsible on a day-to-day basis
                                 for investment of the Fund's portfolio in
                                 accordance with its investment objective and
                                 policies. Calamos makes all investment
                                 decisions for the Fund and places purchase and
                                 sale orders for the Fund's portfolio
                                 securities. As of August 31, 2005, Calamos
                                 managed approximately $41 billion in assets of
                                 individuals and institutions. Calamos is an
                                 indirect subsidiary of Calamos Asset
                                 Management, Inc., whose voting shares are
                                 majority-owned by Calamos Family Partners,
                                 Inc., which is controlled by John P. Calamos,
                                 Sr. and the Calamos family.

                                 The Fund pays Calamos an annual fee, payable
                                 monthly, for its investment management services
                                 equal to 1.00% of the Fund's average weekly
                                 managed assets. See "Management of the Fund."

PORTFOLIO MANAGERS............   John P. Calamos, Sr., Nick P. Calamos and John
                                 P. Calamos, Jr. are responsible for managing
                                 the Fund's portfolio. During the past five
                                 years, John P. Calamos, Sr. has been a
                                 Chairman, CEO and Co-Chief Investment Officer
                                 of Calamos; Nick P. Calamos has been a Senior
                                 Executive Vice President and Co-Chief
                                 Investment Officer of Calamos; and John P.
                                 Calamos, Jr. has been an Executive Vice
                                 President of Calamos.

LISTING.......................   The common shares have been approved for
                                 listing on the New York Stock Exchange under
                                 the symbol "CGO."

6

CUSTODIAN, TRANSFER AGENT AND

DIVIDEND DISBURSING AGENT.....   The Bank of New York will serve as the Fund's
                                 custodian, transfer agent and dividend
                                 disbursing agent. See "Custodian, Transfer
                                 Agent and Dividend Disbursing Agent."

FUND ACCOUNTING...............   State Street Bank and Trust Company ("State
                                 Street") and Calamos will provide fund
                                 accounting and financial accounting services to
                                 the Fund.

MARKET PRICE OF COMMON
SHARES........................   Common shares of closed-end investment
                                 companies frequently trade at prices lower than
                                 their net asset value. The Fund's net asset
                                 value will be reduced immediately following
                                 this offering by the sales load and the amount
                                 of the organization and offering expenses paid
                                 by the Fund. See "Use of Proceeds." In addition
                                 to net asset value, the market price of the
                                 Fund's common shares may be affected by such
                                 factors as the Fund's use of leverage, dividend
                                 stability, portfolio credit quality, liquidity,
                                 market supply and demand and the Fund's
                                 dividends paid (which are, in turn, affected by
                                 expenses), call protection for portfolio
                                 securities and interest rate movements. See
                                 "Leverage," "Risk Factors" and "Description of
                                 Shares." The Fund's common shares are designed
                                 primarily for long-term investors, and you
                                 should not purchase common shares if you intend
                                 to sell them shortly after purchase.

DISTRIBUTIONS.................   The Fund intends to distribute to common
                                 shareholders all or a portion of its net
                                 investment income monthly and net realized
                                 capital gains, if any, at least annually. The
                                 first distribution is expected to be declared
                                 approximately 60 days and paid approximately 90
                                 days after the completion of this offering,
                                 depending on market conditions.

                                 The Fund currently intends to make monthly
                                 distributions to common shareholders at a level
                                 rate established by the Board of Trustees. The
                                 rate may be modified by the Board of Trustees
                                 from time to time. Monthly distributions may
                                 include net investment income, net realized
                                 short-term capital gain and, if necessary,
                                 return of capital. Net realized short-term
                                 capital gains distributed to shareholders will
                                 be taxed as ordinary income. In addition, one
                                 distribution per calendar year may include net
                                 realized long-term capital gains. There is no
                                 guarantee that the Fund will realize capital
                                 gains in any given year. Pursuant to the
                                 requirements of the 1940 Act and other
                                 applicable laws, a notice would accompany each
                                 monthly distribution with respect to the
                                 estimated source of the distribution made.
                                 Distributions are subject to
                                 re-characterization for federal income tax
                                 purposes after the end of the fiscal year. The
                                 Fund may at times in its discretion pay out
                                 less than the entire amount of net investment
                                 income earned in any particular period and may
                                 at times pay out such accumulated undistributed
                                 income in addition to net investment income
                                 earned in other periods in order to permit the
                                 Fund to maintain its level distribution policy.
                                 As a result, the dividend paid by the Fund to
                                 holders of common shares for any particular
                                 period may be more or less than the amount of
                                 net investment income earned by the Fund during
                                 such period.

                                        7

                                 In January 2004, Calamos, on behalf of itself
                                 and certain funds, filed an exemptive
                                 application with the Commission seeking an
                                 order under the 1940 Act permitting those funds
                                 to make periodic distributions of long-term
                                 capital gains. The application may be amended
                                 to include the Fund. There can be no assurance
                                 that the Commission will grant such an order.
                                 The staff of the Commission has indicated that
                                 it has suspended the processing of exemptive
                                 applications requesting the type of relief
                                 referenced above, pending review by the staff
                                 of the results of an industry-wide inspection
                                 focusing on the dividend practices of
                                 closed-end investment companies. There can be
                                 no assurance as to when that review might be
                                 completed or whether, following that review,
                                 the staff would process such applications or
                                 grant such relief.

                                 Pursuant to the Fund's Automatic Dividend
                                 Reinvestment Plan, unless a shareholder is
                                 ineligible or elects to receive distributions
                                 in cash, all dividends and capital gains
                                 distributions are automatically reinvested in
                                 additional common shares of the Fund. Since not
                                 all investors can participate in the Automatic
                                 Dividend Reinvestment Plan, you should contact
                                 your broker or nominee to confirm that you are
                                 eligible to participate in the plan. See
                                 "Dividends and Distributions; Automatic
                                 Dividend Reinvestment Plan."

RISKS.........................   No Operating History.  The Fund is a newly
                                 organized closed-end management investment
                                 company and has no operating history or history
                                 of public trading.

                                 Market Price of Shares.  Shares of closed-end
                                 funds frequently trade at a market price that
                                 is below their net asset value. This is
                                 commonly referred to as "trading at a
                                 discount." This characteristic of shares of
                                 closed-end funds is a risk separate and
                                 distinct from the risk that the Fund's net
                                 asset value may decrease. Investors who sell
                                 their shares within a relatively short period
                                 after completion of the public offering are
                                 likely to be exposed to this risk. Accordingly,
                                 the Fund is designed primarily for long-term
                                 investors and should not be considered a
                                 vehicle for trading purposes. Following the
                                 offering, net asset value will be reduced by
                                 the sales load and the amount of organizational
                                 and offering expenses paid by the Fund.
                                 Immediately following any offering of preferred
                                 shares, net asset value will be reduced by the
                                 costs of that offering paid by the Fund. See
                                 "Risk Factors -- Market Price of Shares."

                                 Equity Securities.  Equity investments are
                                 subject to greater fluctuations in market value
                                 than other asset classes as a result of such
                                 factors as the issuer's business performance,
                                 investor perceptions, stock market trends and
                                 general economic conditions. Equity securities
                                 are subordinated to bonds and other debt
                                 instruments in a company's capital structure in
                                 terms of priority to corporate income and
                                 liquidation payments. The Fund may invest in
                                 preferred stocks and convertible securities of
                                 any rating, including below investment grade.

                                        8

                                 High Yield Securities.  The Fund may invest in
                                 high yield securities of any rating. Investment
                                 in high yield securities involves substantial
                                 risk of loss. Below investment grade
                                 non-convertible debt securities or comparable
                                 unrated securities are commonly referred to as
                                 "junk bonds" and are considered predominantly
                                 speculative with respect to the issuer's
                                 ability to pay interest and principal and are
                                 susceptible to default or decline in market
                                 value due to adverse economic and business
                                 developments. The market values for high yield
                                 securities tend to be very volatile, and these
                                 securities are less liquid than investment
                                 grade debt securities. For these reasons, your
                                 investment in the Fund is subject to the
                                 following specific risks:

                                 - increased price sensitivity to changing
                                   interest rates and to a deteriorating
                                   economic environment;

                                 - greater risk of loss due to default or
                                   declining credit quality;

                                 - adverse company specific events are more
                                   likely to render the issuer unable to make
                                   interest and/or principal payments; and

                                 - if a negative perception of the high yield
                                   market develops, the price and liquidity of
                                   high yield securities may be depressed. This
                                   negative perception could last for a
                                   significant period of time.

                                 Adverse changes in economic conditions are more
                                 likely to lead to a weakened capacity of a high
                                 yield issuer to make principal payments and
                                 interest payments than an investment grade
                                 issuer. The principal amount of high yield
                                 securities outstanding has proliferated in the
                                 past decade as an increasing number of issuers
                                 have used high yield securities for corporate
                                 financing. An economic downturn could severely
                                 affect the ability of highly leveraged issuers
                                 to service their debt obligations or to repay
                                 their obligations upon maturity.

                                 The secondary market for high yield securities
                                 may not be as liquid as the secondary market
                                 for more highly rated securities, a factor that
                                 may have an adverse effect on the Fund's
                                 ability to dispose of a particular security.
                                 There are fewer dealers in the market for high
                                 yield securities than for investment grade
                                 obligations. The prices quoted by different
                                 dealers may vary significantly and the spread
                                 between the bid and asked price is generally
                                 much larger than for higher quality
                                 instruments. Under adverse market or economic
                                 conditions, the secondary market for high yield
                                 securities could contract further, independent
                                 of any specific adverse changes in the
                                 condition of a particular issuer, and these
                                 instruments may become illiquid. As a result,
                                 the Fund could find it more difficult to sell
                                 these securities or may be able to sell the
                                 securities only at prices lower than if such
                                 securities were widely traded. Prices realized
                                 upon the sale of such lower rated or unrated
                                 securities, under these circumstances, may be
                                 less than the prices used in calculating the
                                 Fund's net asset value. See "Risk
                                 Factors -- High Yield Securities."

                                 Foreign Securities.  Investments in non-U.S.
                                 issuers may involve unique risks compared to
                                 investing in securities of U.S. issuers. These
                                 risks are more pronounced to the extent that
                                 the Fund

                                        9

                                 invests a significant portion of its non-U.S.
                                 investments in one region or in the securities
                                 of emerging market issuers. These risks may
                                 include:

                                 - less information about non-U.S. issuers or
                                   markets may be available due to less rigorous
                                   disclosure or accounting standards or
                                   regulatory practices;

                                 - many non-U.S. markets are smaller, less
                                   liquid and more volatile and therefore in a
                                   changing market, Calamos may not be able to
                                   sell the Fund's portfolio securities at
                                   times, in amounts and at prices it considers
                                   reasonable;

                                 - the economies of non-U.S. countries may grow
                                   at slower rates than expected or may
                                   experience a downturn or recession;

                                 - economic, political and social developments
                                   may adversely affect the securities markets,
                                   including expropriation and nationalization;

                                 - the difficulty in obtaining or enforcing a
                                   court judgment in non-U.S. countries;

                                 - restrictions on foreign investments in
                                   non-U.S. jurisdictions;

                                 - difficulties in effecting the repatriation of
                                   capital invested in non-U.S. countries;

                                 - withholding and other non-U.S. taxes may
                                   decrease the Fund's return; and

                                 - dividend income the Fund receives from
                                   foreign securities may not be eligible for
                                   the special tax treatment applicable to
                                   qualified dividend income.

See "Risk Factors -- Foreign Securities."

Currency Risk. The value of the securities denominated or quoted in foreign currencies may be adversely affected by fluctuations in the relative currency exchange rates and by exchange control regulations. The Fund's investment performance may be negatively affected by a devaluation of a currency in which the Fund's investments are denominated or quoted. Further, the Fund's investment performance may be significantly affected, either positively or negatively, by currency exchange rates because the U.S. dollar value of securities denominated or quoted in another currency will increase or decrease in response to changes in the value of such currency in relation to the U.S. dollar.

Interest Rate Risk. In addition to the risks discussed above, debt securities, including high yield securities, are subject to certain risks, including the following:

- If interest rates go up, the value of debt securities in the Fund's portfolio generally will decline.

- During periods of declining interest rates, the issuer of a security may exercise its option to prepay principal earlier than scheduled, forcing the Fund to reinvest in lower yielding securities. This is known as call or prepayment risk. Debt securities frequently have call features that allow the issuer to repurchase the security prior to its stated maturity. An issuer

10

may redeem an obligation if the issuer can refinance the debt at a lower cost due to declining interest rates or an improvement in the credit standing of the issuer.

- During periods of rising interest rates, the average life of certain types of securities may be extended because of slower than expected principal payments. This may lock in a below market interest rate, increase the security's duration (the estimated period until the security is paid in full) and reduce the value of the security. This is known as extension risk.

- Rising interest rates could result in an increase in the cost of the Funds' leverage and could adversely affect the ability of the Fund to meet asset coverage requirements with respect to leverage.

Default Risk. Default risk refers to the risk that a company that issues a debt security will be unable to fulfill its obligations to repay principal and interest. The lower a debt security is rated, the greater the default risk.

Illiquid Investments. The Fund may invest up to 15% of its managed assets in securities that, at the time of investment, are illiquid (determined using the Commission's standard applicable to investment companies, i.e., securities that cannot be disposed of within 7 days in the ordinary course of business at approximately the value at which the Fund has valued the securities). The Fund may also invest without limit in Rule 144A Securities. Calamos, under the supervision of the Board of Trustees, will determine whether Rule 144A Securities are illiquid (that is, not readily marketable) and thus subject to the Fund's limit on investing no more than 15% of its managed assets in illiquid securities. Investments in Rule 144A Securities could have the effect of increasing the amount of the Fund's assets invested in illiquid securities if qualified institutional buyers are unwilling to purchase these Rule 144A Securities. Illiquid securities may be difficult to dispose of at a fair price at the times when the Fund believes it is desirable to do so. Investment of the Fund's assets in illiquid securities may restrict the Fund's ability to take advantage of other market opportunities. The market price of illiquid securities generally is more volatile than that of more liquid securities, which may adversely affect the price that the Fund pays for or recovers upon the sale of illiquid securities. Illiquid securities are also more difficult to value and Calamos' judgment may play a greater role in the valuation process. The risks associated with illiquid securities may be particularly acute in situations in which the Fund's operations require cash and could result in the Fund borrowing to meet its short-term needs or incurring losses on the sale of illiquid securities.

Convertible Securities. Convertible securities generally offer lower interest or dividend yields than non-convertible securities of similar quality. The market values of convertible securities tend to decline as interest rates increase and, conversely, to increase as

11

interest rates decline. However, the convertible security's market value tends to reflect the market price of the common stock of the issuing company when that stock price is greater than the convertible security's "conversion price." The conversion price is defined as the predetermined price at which the convertible security could be exchanged for the associated stock. As the market price of the underlying common stock declines, the price of the convertible security tends to be influenced more by the yield of the convertible security. Thus, it may not decline in price to the same extent as the underlying common stock. In the event of a liquidation of the issuing company, holders of convertible securities would be paid before the company's common stockholders. Consequently, the issuer's convertible securities generally entail less risk than its common stock.

Synthetic Convertible Instruments. The value of a synthetic convertible instrument may respond differently to market fluctuations than a convertible security because a synthetic convertible instrument is composed of two or more separate securities, each with its own market value. In addition, if the value of the underlying common stock or the level of the index involved in the convertible component falls below the exercise price of the warrant or option, the warrant or option may lose all value. Synthetic convertible instruments created by other parties have the same attributes of a convertible security, however, the issuer of the synthetic convertible instrument assumes the credit risk associated with the investment, rather than the issuer of the underlying equity security into which the instrument is convertible. Therefore, the Fund is subject to the credit risk associated with the party creating the synthetic convertible instrument.

Risks Associated with Options. There are several risks associated with transactions in options. For example, there are significant differences between the securities and options markets that could result in an imperfect correlation among these markets, causing a given transaction not to achieve its objectives. A decision as to whether, when and how to use options involves the exercise of skill and judgment, and even a well-conceived transaction may be unsuccessful to some degree because of market behavior or unexpected events. The Fund's ability to utilize options successfully will depend on Calamos' ability to predict pertinent market movements, which cannot be assured.

The Fund's ability to close out its position as a purchaser or seller of an Options Clearing Corporation ("OCC") or exchange listed put or call option is dependent, in part, upon the liquidity of the option market. Among the possible reasons for the absence of a liquid option market are: (i) insufficient trading interest in certain options; (ii) restrictions on transactions imposed by an exchange; (iii) trading halts, suspensions or other restrictions imposed with respect to particular classes or series of options or underlying securities, including reaching daily price limits; (iv) interruption of the normal operations of the OCC or an exchange; (v) inadequacy of the facilities of an exchange or

12

OCC to handle current trading volume; or (vi) a decision by one or more exchanges to discontinue the trading of options (or a particular class or series of options), in which event the relevant market for that option on that exchange would cease to exist, although outstanding options on that exchange would generally continue to be exercisable in accordance with their terms. If the Fund were unable to close out an option that it had purchased on a security, it would have to exercise the option in order to realize any profit or the option would expire and become worthless. If the Fund were unable to close out a covered call option that it had written on a security, it would not be able to sell the underlying security until the option expired. As the writer of a covered call option on a security, the Fund foregoes, during the option's life, the opportunity to profit from increases in the market value of the security covering the call option above the sum of the premium and the exercise price of the call.

The hours of trading for listed options may not coincide with the hours during which the underlying financial instruments are traded. To the extent that the option markets close before the markets for the underlying financial instruments, significant price and rate movements can take place in the underlying markets that cannot be reflected in the option markets until the next trading day.

Unless the parties provide for it, there is no central clearing or guaranty function in an over-the-counter ("OTC") option. As a result, if the counterparty fails to make or take delivery of the security or other instrument underlying an OTC option it has entered into with the Fund or fails to make a cash settlement payment due in accordance with the terms of that option, the Fund will lose any premium it paid for the option as well as any anticipated benefit of the transaction. Accordingly, Calamos must assess the creditworthiness of each such counterparty or any guarantor or credit enhancement of the counterparty's credit to determine the likelihood that the terms of the OTC option will be satisfied. The Fund will engage in OTC option transactions only with U.S. government securities dealers recognized by the Federal Reserve Bank of New York as "primary dealers" or broker/dealers, domestic or foreign banks or other financial institutions that have received (or the guarantors of the obligation of which have received) a short-term credit rating of A-1 from Standard & Poor's or P-1 from Moody's or an equivalent rating from any nationally recognized statistical rating organization ("NRSRO") or, in the case of OTC currency transactions, are determined to be of equivalent credit quality by Calamos.

The Fund may sell call options on individual securities and securities indices. All calls sold by the Fund must be "covered." Even though the Fund will receive the option premium to help protect it against loss, a call option sold by the Fund exposes the Fund during the term of the option to possible loss of opportunity to realize appreciation in the market price of the underlying security or instrument in excess of the exercise or strike price and

13

may require the Fund to hold a security or instrument that it might otherwise have sold. The Fund may purchase and sell put options on individual securities and securities indices. In selling put options, there is a risk that the Fund may be required to buy the underlying security at a disadvantageous price above the market price.

Leverage. The Fund may use leverage by issuing preferred shares, borrowing money or issuing debt securities. The Fund currently anticipates that it will issue cumulative preferred shares, as soon as practicable after the closing of this offering, with an aggregate liquidation preference of up to approximately 33% of the Fund's total assets immediately after issuance. As a non-fundamental policy, such preferred shares, borrowings or debt securities may not exceed 38% of the Fund's total assets. The Fund may not be leveraged at all times and the amount of borrowing or leverage, if any, may vary depending upon a variety of factors, including Calamos' outlook for the market and the costs that the Fund would incur as a result of such leverage. Leverage creates risks that may adversely affect the return for the holders of common shares, including:

- the likelihood of greater volatility of net asset value and market price of the Fund's common shares;

- fluctuations in the dividend rates on any preferred shares or in interest rates on borrowings and debt securities;

- increased operating costs, which are effectively borne by common shareholders, may reduce the Fund's total return; and

- the potential for a decline in the value of an investment acquired with proceeds from leverage, while the Fund's obligations under such leverage remain fixed.

To the extent the income or capital appreciation derived from securities purchased with funds received from leverage exceeds the cost of leverage, the Fund's return will be greater than if leverage had not been used. Conversely, if the income or capital appreciation from the securities purchased with such funds is not sufficient to cover the cost of leverage or if the Fund incurs capital losses, the return of the Fund will be less than if leverage had not been used, and therefore the amount available for distribution to common shareholders as dividends and other distributions will be reduced or potentially eliminated. Common shareholders bear the costs of any leverage.

Certain types of borrowings may result in the Fund being subject to covenants in credit agreements, including those relating to asset coverage, borrowing base and portfolio composition requirements and additional covenants that may affect the Fund's ability to pay dividends and distributions on common shares in certain instances and may affect the Fund's implementation of its investment strategy. The Fund may also be required to pledge its assets to the lenders in connection with certain types of borrowings. The Fund may be subject to certain restrictions on investments imposed by guidelines of one or more NRSROs that may issue ratings for the

14

preferred shares or short-term debt instruments issued by the Fund. These guidelines may impose asset coverage or portfolio composition requirements that are more stringent than those imposed by the 1940 Act. See "Risk Factors -- Leverage."

Interest Rate Transactions Risk. The Fund may enter into an interest rate swap or cap transaction to attempt to protect itself from increasing dividend or interest expenses on its leverage resulting from increasing short-term interest rates. A decline in interest rates may result in a decline in the value of the swap or cap, which may result in a decline in the net asset value of the Fund. See "Risk Factors -- Interest Rate Transactions Risk."

Tax Risk. The Fund may invest in certain securities, such as certain convertible and high yield securities, for which the federal income tax treatment may not be clear or may be subject to recharacterization by the Internal Revenue Service ("IRS"). It could be more difficult for the Fund to comply with the tax requirements applicable to regulated investment companies if the tax characterization of the Fund's investments are not clear or if the tax treatment of the income from such investments were successfully challenged by the IRS. See "Risk Factors -- Tax Risk" and "U.S. Federal Income Tax Matters."

Management Risk. Calamos' judgment about the attractiveness, relative value or potential appreciation of a particular sector, security or investment strategy may prove to be incorrect.

Antitakeover Provisions. The Fund's Agreement and Declaration of Trust and By-Laws include provisions that could limit the ability of other entities or persons to acquire control of the Fund or to change the composition of its Board of Trustees. Such provisions could limit the ability of shareholders to sell their shares at a premium over prevailing market prices by discouraging a third party from seeking to obtain control of the Fund. These provisions include staggered terms of office for the Trustees, advance notice requirements for shareholder proposals, and super-majority voting requirements for certain transactions with affiliates, converting the Fund to an open-end investment company or a merger, asset sale or similar transaction. Holders of preferred shares will have voting rights in addition to and separate from the voting rights of common shareholders with respect to certain of these matters. See "Description of Shares -- Preferred Shares" and "Certain Provisions of the Agreement and Declaration of Trust and By-Laws." The holders of preferred shares, on the one hand, and the holders of the common shares, on the other, may have interests that conflict in these situations.

Market Disruption Risk. Certain events have a disruptive effect on the securities markets, such as terrorist attacks (including the terrorist attacks in the United States on September 11, 2001), war and other geopolitical events, earthquakes, storms and other disasters. The Fund cannot predict the effects of similar events in the future on the markets or economy of the U.S. or other countries.

15

SUMMARY OF FUND EXPENSES

The following table shows the Fund's expenses as a percentage of net assets attributable to common shares assuming the Fund issues preferred shares in an amount equal to 33% of the Fund's total assets immediately after issuance.

SHAREHOLDER TRANSACTION EXPENSES:

Sales Load Paid by You (as a percentage of offering
  price)....................................................        4.50%
Offering Expenses of the Common Shares borne by the Fund
  (as a percentage of offering price)(1)....................        0.20%
Offering Expenses of the Preferred Shares expected to be
  borne by the Fund
  (as a percentage of offering price)(2)....................        0.76%
Dividend Reinvestment Plan Fees.............................      None(3 )

                                                               PERCENTAGE OF
                                                                 NET ASSETS
                                                              ATTRIBUTABLE TO
                                                               COMMON SHARES
                                                                  (ASSUMES
                                                              PREFERRED SHARES
                                                               ARE ISSUED)(4)
                                                              ----------------
ANNUAL EXPENSES:
     Management Fee.........................................       1.50%
     Other Expenses.........................................        .60%
     Interest Payments on Leverage Instruments(5)...........       1.90%
                                                                   ----
     Total Annual Expenses..................................       4.00%


(1) Calamos has agreed to pay organizational expenses and offering costs (other than sales load, but including reimbursement of underwriter expenses of $0.005 per share) that exceed $0.03 per common share (0.20% of the offering price).

(2) If the Fund offers preferred shares, costs of that offering, estimated to be approximately 1.59% of the total amount of the preferred share offering (including the sales load paid to the underwriters in connection with the preferred shares offering) will effectively be borne by the common shareholders and will result in a reduction of the net asset value of the common shares. Assuming the issuance of preferred shares in the amount equal to 33% of the Fund's total assets immediately after issuance, those offering costs are estimated to be approximately $0.11 per common share (0.76% of the offering price of the common shares).

(3) A shareholder that directs the plan agent to sell shares held in a dividend reinvestment account will pay brokerage charges.

(4) If the Fund does not issue preferred shares, or otherwise use leverage, the Fund's expenses would be:

                                                               PERCENTAGE OF
                                                                NET ASSETS
                                                              ATTRIBUTABLE TO
                                                               COMMON SHARES
                                                              ---------------
ANNUAL EXPENSES:
    Management Fee..........................................       1.00%
    Other Expenses..........................................       0.33%
                                                                   ----
    Total Annual Expenses...................................       1.33%

(5) Assumes a dividend rate on preferred shares of 3.80%. Such rate is an estimate and may differ based on varying market conditions that may exist as and when the preferred shares are offered. In the event the Fund, as an alternative to issuing preferred shares, utilizes leverage through borrowings in an amount equal to 33% of the Fund's total assets (including the amount obtained from leverage), it is estimated that, as a percentage of net assets attributable to common shares, the "Management Fee" would be 1.50%, "Other Expenses" would be 0.38%, "Interest Payments on Leverage Instruments" (assuming an interest rate of 5.00%, which interest rate is subject to change based on prevailing market conditions) would be 2.50% and "Total Annual Expenses" would be

16

4.38%. Based on the "Total Annual Expenses" and in accordance with the example below, the expenses for years 1, 3, 5 and 10 would be $89, $173, $259 and $478, respectively.

The purpose of the table above is to help you understand all fees and expenses that you, as a common shareholder, would bear directly or indirectly. As of the date of this prospectus, the Fund has not commenced investment operations. The amount set forth under "Other Expenses" is based upon estimates for the current fiscal year. The table assumes that the Fund issues 5,000,000 common shares and issues preferred shares as a means of leverage. If the Fund issues fewer common shares, all other things being equal, these expenses, as a percentage of net assets, would increase. If the Fund utilizes leverage through borrowing, the Fund would incur interest expense. For additional information with respect to the Fund's expenses, see "Management of the Fund." Other expenses include custodial and transfer agency fees, legal and accounting expenses, and listing fees.

EXPENSE EXAMPLE: The following example illustrates the expenses (including the sales load of $45, estimated offering and organizational expenses of this offering of $2.00 and the estimated preferred share offering costs of $7.59, assuming preferred shares are issued representing 33% of the Fund's total assets) that you would pay on a $1,000 investment in common shares, assuming (1) total annual expenses of 4.00% of net assets attributable to common shares, (2) a 5% annual return and (3) the Fund issues preferred shares in an amount equal to 33% of the Fund's total assets:(*)

                                                              1 YEAR   3 YEARS   5 YEARS   10 YEARS
                                                              ------   -------   -------   --------
Total Expenses You Would Pay................................   $93      $170      $250       $455


(*) THE EXAMPLE SHOULD NOT BE CONSIDERED A REPRESENTATION OF FUTURE EXPENSES.
ACTUAL EXPENSES MAY BE GREATER OR LESS THAN THOSE ASSUMED. The example assumes that the estimated "Other Expenses" set forth in the fee table are accurate and that all dividends and distributions are reinvested at net asset value. Moreover, the Fund's actual rate of return may be greater or less than the hypothetical 5% return shown in the example. The expenses you would pay, based on the Fund's expenses stated as a percentage of the Fund's net assets assuming the Fund does not issue preferred shares, or otherwise use leverage, and otherwise making the same assumptions in the example above, would be: 1 year, $60; 3 years, $87; 5 years, $116; and 10 years, $200.

THE FUND

Calamos Global Total Return Fund is a newly organized, diversified, closed-end management investment company. The Fund was organized under the laws of the state of Delaware on March 30, 2004, and has registered under the 1940 Act. As a recently organized entity, the Fund has no operating history. The Fund's principal office is located at 2020 Calamos Court, Naperville, Illinois 60563, and its telephone number is 1-800-582-6959.

USE OF PROCEEDS

The net proceeds of this offering will be approximately $ (or approximately $ assuming the underwriters exercise the overallotment option in full) after payment of organizational and offering costs estimated to be approximately $ and the deduction of the sales load. Calamos has agreed to pay organizational expenses and offering costs (other than sales load, but including reimbursement of underwriter expenses of $0.005 per share) that exceed $0.03 per share.

The Fund will invest the net proceeds of the offering in accordance with the Fund's investment objective and policies as stated below. It is presently anticipated that the Fund will invest substantially all of the net proceeds in securities that meet the investment objective and policies within three months after completion of this offering. Pending such investment, the Fund anticipates that all or a portion of the proceeds will be invested in U.S. government securities or high grade, short-term money market instruments. If necessary, the Fund may also purchase, as temporary investments, securities of other

17

open- or closed-end investment companies that invest primarily in the types of securities in which the Fund may invest directly. See "Investment Objective and Principal Investment Strategies."

INVESTMENT OBJECTIVE AND PRINCIPAL INVESTMENT STRATEGIES

INVESTMENT OBJECTIVE

The Fund's investment objective is to provide total return through a combination of capital appreciation and current income. The Fund's investment objective may be changed by its Board of Trustees without a shareholder vote, except that the Fund will give shareholders at least 60 days' notice of any change to the Fund's investment objective. The Fund makes no assurance that it will realize its objective. An investment in the Fund may be speculative in that it involves a high degree of risk and should not constitute a complete investment program. See "Risk Factors."

PRINCIPAL INVESTMENT STRATEGIES

Under normal circumstances, the Fund will invest primarily in a portfolio of common and preferred stocks, convertible securities and income producing securities such as investment grade and below investment grade (high yield/high risk) debt securities. The Fund, under normal circumstances, will invest at least 50% of its managed assets in equity securities (including securities that are convertible into equity securities). The Fund may invest up to 100% of its managed assets in securities of foreign issuers, including debt and equity securities of corporate issuers and debt securities of government issuers, in developed and emerging markets. Under normal circumstances, the Fund will invest at least 30% of its managed assets in securities of foreign issuers. The Fund will invest in the securities of issuers of several different countries throughout the world, in addition to the United States.

Calamos will dynamically allocate the Fund's investments among multiple asset classes (rather than maintaining a fixed or static allocation), seeking to obtain an appropriate balance of risk and reward through all market cycles using multiple strategies and combining them to seek to achieve favorable risk adjusted returns.

The Fund will attempt to keep a consistent balance between risk and reward over the course of different market cycles, through various combinations of stocks, bonds, and/or convertible securities, to achieve what Calamos believes to be an appropriate blend for the then current market. As the market environment changes, portfolio securities may change in an attempt to achieve a relatively consistent risk level over time. At some points in a market cycle, one type of security may make up a substantial portion of the Fund's portfolio, while at other times certain securities may have minimal or no representation, depending on market conditions.

The Fund may also seek to generate income from option premiums by writing (selling) options (with an aggregate notional value of up to 33% of the value of the Fund's managed assets). The Fund will opportunistically employ a strategy of writing options. The extent of option writing activity will depend upon market conditions and Calamos' ongoing assessment of the attractiveness of writing options on the Fund's equity holdings.

EQUITY SECURITIES. Equity securities include common and preferred stocks, warrants, rights, and depository receipts. Under normal circumstances, the Fund will invest at least 50% of its managed assets in equity securities (including securities that are convertible into equity securities). The Fund may invest in preferred stocks and convertible securities of any rating, including below investment grade. See "-- High Yield Securities" below. An investment in the equity securities of a company represents a proportionate ownership interest in that company. Therefore, the Fund participates in the financial success or failure of any company in which it has an equity interest.

HIGH YIELD SECURITIES. The Fund may invest in high yield securities for either current income or capital appreciation or both. The high yield securities in which the Fund invests are rated below investment grade (i.e., rated Ba or lower by Moody's or BB or lower by S&P's) or are unrated but determined by Calamos to be of comparable quality. The Fund expects that it initially will invest

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approximately 30% of its managed assets in high yield securities, which percentage may change over time. The Fund may invest in high yield securities of any rating. Non-convertible debt securities rated below investment grade are commonly referred to as "junk bonds" and are considered speculative with respect to the issuer's capacity to pay interest and repay principal. Below investment grade non-convertible debt securities involve greater risk of loss, are subject to greater price volatility and are less liquid, especially during periods of economic uncertainty or change, than higher rated debt securities.

OTHER INCOME SECURITIES. The Fund may also invest in investment grade income securities. The Fund's investments in investment grade income securities may have fixed or variable principal payments and all types of interest rate and dividend payment and reset terms, including fixed rate, adjustable rate, zero coupon, contingent, deferred, payment in kind and auction rate features.

FOREIGN SECURITIES. The Fund may invest up to 100% of its managed assets in securities of foreign issuers, including debt and equity securities of corporate issuers and debt securities of government issuers, in developed and emerging markets. The Fund expects that it initially will invest more than 50% of its managed assets in securities of foreign issuers, which percentage may change over time, depending on Calamos' ongoing assessment of market opportunities for the Fund. Under normal circumstances, the Fund will invest at least 30% of its managed assets in securities of foreign issuers. The Fund will invest in the securities of issuers of several different countries throughout the world, in addition to the United States. A foreign issuer is a company organized under the laws of a foreign country.

CONVERTIBLE SECURITIES. The Fund may invest in convertible securities. A convertible security is a debt security or preferred stock that is exchangeable for an equity security (typically of the same issuer) at a predetermined price (the "conversion price") or a security that mandatorily converts to an equity security at a predetermined time. Depending upon the relationship of the conversion price to the market value of the underlying security, a convertible security may trade more like an equity security than a debt instrument. The Fund may invest in convertible securities of any rating including below investment grade. See "-- High Yield Securities" above. Securities that are convertible into equity securities are considered equity-securities for purposes of the Fund's policy to invest at least 50% of its managed assets in equity securities.

SYNTHETIC CONVERTIBLE INSTRUMENTS. Calamos may also establish a "synthetic" convertible instrument by combining separate securities that possess economic characteristics similar to a convertible security, I.E., an income component and the right or obligation to convert to an equity security ("convertible component"). The income component is achieved by investing in non-convertible, fixed-income securities such as bonds, preferred stocks, money market instruments and other instruments that provide an income component. The convertible component is achieved by investing in warrants or options to buy common stock at a certain exercise price, or options on a stock index. In establishing a synthetic instrument, Calamos may also pool a basket of fixed-income securities and a basket of warrants or options that produce the economic characteristics similar to a convertible security. Within each basket of fixed-income securities and warrants or options, different companies may issue the fixed-income and convertible components, which may be purchased separately and at different times.

The Fund may also purchase synthetic convertible instruments created by other parties, typically investment banks, including convertible structured notes. Convertible structured notes are fixed income debentures linked to equity. Convertible structured notes have the attributes of a convertible security; however, the investment bank that issued the convertible note assumes the credit risk associated with the investment, rather than the issuer of the underlying common stock into which the note is convertible. Purchasing synthetic convertible instruments may offer more flexibility than purchasing a convertible security. Different companies may issue the fixed-income and convertible components, which may be purchased separately and at different times. The Fund's holdings of synthetic convertible instruments are considered equity securities for purposes of the Fund's policy to invest at least 50% of its managed assets in equity securities. If the Fund purchases a synthetic convertible instrument, a component of which is an option, such option will not be considered an option for the purpose of the Fund's limitations on options described below.

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OPTIONS. STRATEGY. The Fund may seek to generate income from option premiums by writing (selling) options (with an aggregate notional value of up to 33% of the value of the Fund's managed assets). The Fund may write (sell) call options (i) on a portion of the equity securities (including securities that are convertible into equity securities) in the Fund's portfolio and (ii) on broad-based securities indices (such as the S&P 500 or MSCI EAFE) or certain ETFs (exchange traded funds) that trade like common stocks but seek to replicate such market indices.

In addition, to seek to offset some of the risk of a large potential decline in the event the overall stock market has a sizeable short-term or intermediate-term decline, the Fund may also, to a limited extent, purchase put options (with an aggregate notional value of not more than 5% of the value of the Fund's managed assets) on broad-based securities indices (such as the S&P 500 or MSCI EAFE) or certain ETFs (exchange-traded funds) that trade like common stocks but seek to replicate such market indices.

OPTIONS IN GENERAL. A call option, upon payment of a premium, gives the purchaser of the option the right to buy, and the seller the obligation to sell, the underlying security, index or other instrument at the exercise price. A put option gives the purchaser of the option, upon payment of a premium, the right to sell, and the seller the obligation to buy, the underlying security, index, or other instrument at the exercise price.

The Fund is authorized to purchase and sell exchange listed options and over-the-counter options ("OTC options"). Exchange listed options are issued by a regulated intermediary such as the OCC, which guarantees the performance of the obligations of the parties to such options. In addition, the Fund may purchase instruments structured by broker-dealers or investment banks that package or possess economic characteristics of options. The discussion below uses the OCC as an example, but is also applicable to other financial intermediaries.

With certain exceptions, OCC issued and exchange listed options generally settle by physical delivery of the underlying security, although in the future cash settlement may become available. Index options are cash settled for the net amount, if any, by which the option is "in-the-money" (i.e., where the value of the underlying instrument exceeds, in the case of a call option, or is less than, in the case of a put option, the exercise price of the option) at the time the option is exercised. Frequently, rather than taking or making delivery of the underlying instrument through the process of exercising the option, listed options are closed by entering into offsetting purchase or sale transactions that do not result in ownership of the new option.

OTC options are purchased from or sold to securities dealers, financial institutions or other parties ("Counterparties") through direct bilateral agreement with the Counterparty. In contrast to exchange listed options, which generally have standardized terms and performance mechanics, all the terms of an OTC option, including such terms as method of settlement, term, exercise price, premium, guarantees and security, are set by negotiation of the parties. The Fund may sell OTC options (other than OTC currency options) that are subject to a buy-back provision permitting the Fund to require the Counterparty to sell the option back to the Fund at a formula price within seven days. The Fund expects generally to enter into OTC options that have cash settlement provisions, although it is not required to do so. The staff of the Commission currently takes the position that OTC options purchased by a fund, and portfolio securities "covering" the amount of a fund's obligation pursuant to an OTC option sold by it (or the amount of assets equal to the formula price for the repurchase of the option, if any, less the amount by which the option is in the money) are illiquid. OTC options purchased by the Fund and any portfolio securities used to cover obligations pursuant to such options are not considered illiquid by Calamos for the purposes of the Fund's limitation on investments in illiquid securities.

The Fund may also purchase and sell options on securities indices and other financial indices. Options on securities indices and other financial indices are similar to options on a security or other instrument except that, rather than settling by physical delivery of the underlying instrument, they settle by cash settlement, i.e., an option on an index gives the holder the right to receive, upon exercise of the option, an amount of cash if the closing level of the index upon which the option is based exceeds, in the case of a call, or is less than, in the case of a put, the exercise price of the option (except if, in the case of an OTC option, physical delivery is specified). This amount of cash is equal to the excess of the closing price of

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the index over the exercise price of the option, which also may be multiplied by a formula value. The seller of the option is obligated, in return for the premium received, to make delivery of this amount. The gain or loss on an option on an index depends on price movements in the instruments making upon the market, market segment, industry or other composite on which the underlying index is based, rather than price movements in individual securities, as is the case with respect to options on securities.

The Fund will write call options and put options only if they are "covered." For example, a call option written by the Fund will require the Fund to hold the securities subject to the call (or securities convertible into the needed securities without additional consideration) or to segregate cash or liquid assets sufficient to purchase and deliver the securities if the call is exercised. A call option sold by the Fund on an index will require the Fund to own portfolio securities that correlate with the index or to segregate cash or liquid assets equal to the excess of the index value over the exercise price on a current basis. A put option written by the Fund requires the Fund to segregate cash or liquid assets equal to the exercise price.

OTC options entered into by the Fund will generally provide for cash settlement. As a result, when the Fund sells these instruments it will only segregate an amount of cash or liquid assets equal to its accrued net obligations, as there is no requirement for payment or delivery of amounts in excess of the net amount. These amounts will equal 100% of the exercise price in the case of a non cash-settled put, the same as an OCC guaranteed listed option sold by the Fund, or the in-the-money amount plus any sell-back formula amount in the case of a cash-settled put or call. In addition, when the Fund sells a call option on an index at a time when the in-the-money amount exceeds the exercise price, the Fund will segregate, until the option expires or is closed out, cash or cash equivalents equal in value to such excess. OTC options other than those above may also settle with physical delivery, or with an election of either physical delivery or cash settlement and the Fund will segregate an amount of cash or liquid assets equal to the full value of the option. OTC options settling with physical delivery, or with an election of either physical delivery or cash settlement, will be treated the same as other options settling with physical delivery.

If an option written by the Fund expires, the Fund will generally realize a capital gain equal to the premium received at the time the option was written. If an option purchased by the Fund expires, the Fund realizes a capital loss equal to the premium paid.

The Fund will generally realize a capital gain from a closing purchase transaction if the cost of the closing option is less than the premium received from writing the option, or, if it is more, the Fund will generally realize a capital loss. If the premium received from a closing sale transaction is more than the premium paid to purchase the option, the Fund will generally realize a capital gain or, if it is less, the Fund will generally realize a capital loss. The principal factors affecting the market value of a put or a call option include supply and demand, interest rates, the current market price of the underlying security or index in relation to the exercise price of the option, the volatility of the underlying security or index, and the time remaining until the expiration date.

A put option purchased by the Fund is an asset of the Fund, valued initially at the premium paid for the option. The premium received for an option written by the Fund is recorded as a deferred credit. The value of an option purchased or written is marked-to-market daily and is valued at the closing price on the exchange on which it is traded or, if not traded on an exchange or no closing price is available, at the mean between the last bid and asked prices.

RULE 144A SECURITIES. The Fund may invest without limit in Rule 144A Securities. Calamos, under the supervision of the Board of Trustees, will determine whether Rule 144A Securities are illiquid (that is, not readily marketable) and thus subject to the Fund's limit on investing no more than 15% of its managed assets in illiquid securities. A determination of whether a Rule 144A Security is liquid or not is a question of fact. In making this determination, Calamos will consider the trading markets for the specific security, taking into account the unregistered nature of a Rule 144A Security. In addition, Calamos could consider the (1) frequency of trades and quotes, (2) number of dealers and potential purchasers, (3) dealer undertakings to make a market and (4) nature of a security and of marketplace trades (e.g., the time needed to dispose of the security, the method of soliciting offers and the mechanics of transfer).

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The liquidity of Rule 144A Securities will be monitored and, if as a result of changed conditions, it is determined that a Rule 144A Security is no longer liquid, the Fund's holdings of illiquid securities would be reviewed to determine what, if any, steps are required to assure that the Fund does not invest more than 15% of its managed assets in illiquid securities. Investing in Rule 144A Securities could have the effect of increasing the amount of the portfolio's assets invested in illiquid securities if qualified institutional buyers are unwilling to purchase such securities.

U.S. GOVERNMENT SECURITIES. U.S. government securities in which the Fund invests include debt obligations of varying maturities issued by the U.S. Treasury or issued or guaranteed by an agency or instrumentality of the U.S. government, including the Federal Housing Administration, Federal Financing Bank, Farmers Home Administration, Export-Import Bank of the United States, Small Business Administration, Government National Mortgage Association, General Services Administration, Central Bank for Cooperatives, Federal Farm Credit Banks, Federal Home Loan Banks, Federal Home Loan Mortgage Corporation, Federal National Mortgage Association ("FNMA"), Maritime Administration, Tennessee Valley Authority, District of Columbia Armory Board, Student Loan Marketing Association, Resolution Fund Corporation and various institutions that previously were or currently are part of the Farm Credit System (which has been undergoing reorganization since 1987). Some U.S. government securities, such as U.S. Treasury bills, Treasury notes and Treasury bonds, which differ only in their interest rates, maturities and times of issuance, are supported by the full faith and credit of the United States. Others are supported by: (i) the right of the issuer to borrow from the U.S. Treasury, such as securities of the Federal Home Loan Banks; (ii) the discretionary authority of the U.S. government to purchase the agency's obligations, such as securities of the FNMA; or (iii) only the credit of the issuer. No assurance can be given that the U.S. government will provide financial support in the future to U.S. government agencies, authorities or instrumentalities that are not supported by the full faith and credit of the United States. Securities guaranteed as to principal and interest by the U.S. government, its agencies, authorities or instrumentalities include: (i) securities for which the payment of principal and interest is backed by an irrevocable letter of credit issued by the U.S. government or any of its agencies, authorities or instrumentalities; and (ii) participations in loans made to non-U.S. governments or other entities that are so guaranteed. The secondary market for certain of these participations is limited and, therefore, may be regarded as illiquid.

ZERO COUPON SECURITIES. The securities in which the Fund invests may include zero coupon securities, which are debt obligations that are issued or purchased at a significant discount from face value. The discount approximates the total amount of interest the security will accrue and compound over the period until maturity or the particular interest payment date at a rate of interest reflecting the market rate of the security at the time of issuance. Zero coupon securities do not require the periodic payment of interest. These investments benefit the issuer by mitigating its need for cash to meet debt service, but generally require a higher rate of return to attract investors who are willing to defer receipt of cash. These investments may experience greater volatility in market value than U.S. government or other securities that make regular payments of interest. The Fund accrues income on these investments for tax and accounting purposes, which is distributable to shareholders and which, because no cash is received at the time of accrual, may require the liquidation of other portfolio securities to satisfy the Fund's distribution obligations, in which case the Fund will forgo the opportunity to purchase additional income producing assets with the liquidation proceeds. Zero coupon U.S. government securities include STRIPS and CUBES, which are issued by the U.S. Treasury as component parts of U.S. Treasury bonds and represent scheduled interest and principal payments on the bonds.

OTHER INVESTMENT COMPANIES. The Fund may invest in the securities of other investment companies to the extent that such investments are consistent with the Fund's investment objective and policies and are permissible under the 1940 Act. Under the 1940 Act, the Fund may not acquire the securities of other domestic or non-U.S. investment companies if, as a result, (1) more than 10% of the Fund's total assets would be invested in securities of other investment companies, (2) such purchase would result in more than 3% of the total outstanding voting securities of any one investment company being held by the Fund, or (3) more than 5% of the Fund's total assets would be invested in any one investment company. These

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limitations do not apply to the purchase of shares of any investment company in connection with a merger, consolidation, reorganization or acquisition of substantially all the assets of another investment company.

The Fund, as a holder of the securities of other investment companies, will bear its pro rata portion of the other investment companies' expenses, including advisory fees. These expenses are in addition to the direct expenses of the Fund's own operations.

TEMPORARY DEFENSIVE INVESTMENTS. In response to adverse market, economic or political conditions, the Fund may take temporary defensive positions and may invest up to 100% of its total assets in securities issued or guaranteed by the U.S. government or its instrumentalities or agencies, certificates of deposit, bankers' acceptances and other bank obligations, commercial paper rated in the highest category by a NRSRO or other fixed income securities deemed by Calamos to be consistent with a defensive posture, or may hold cash. The yield on such securities may be lower than the yield on lower rated fixed income securities. During such periods, the Fund may not be able to achieve its investment objective.

REPURCHASE AGREEMENTS. The Fund may enter into repurchase agreements with broker-dealers, member banks of the Federal Reserve System and other financial institutions. Repurchase agreements are arrangements under which the Fund purchases securities and the seller agrees to repurchase the securities within a specific time and at a specific price. The repurchase price is generally higher than the Fund's purchase price, with the difference being income to the Fund. The counterparty's obligations under the repurchase agreement are collateralized with U.S. Treasury and/or agency obligations with a market value of not less than 100% of the obligations, valued daily. Collateral is held by the Fund's custodian in a segregated, safekeeping account for the benefit of the Fund. Repurchase agreements afford the Fund an opportunity to earn income on temporarily available cash at low risk. In the event of commencement of bankruptcy or insolvency proceedings with respect to the seller of the security before repurchase of the security under a repurchase agreement, the Fund may encounter delay and incur costs before being able to sell the security. Such a delay may involve loss of interest or a decline in price of the security. If a court characterizes a repurchase transaction as a loan and the Fund has not perfected a security interest in the security, the Fund may be required to return the security to the seller's estate and be treated as an unsecured creditor of the seller. As an unsecured creditor, the Fund would be at risk of losing some or all of the principal and interest involved in the transaction.

LENDING OF PORTFOLIO SECURITIES. The Fund may lend portfolio securities to registered broker-dealers or other institutional investors deemed by Calamos to be of good standing under agreements which require that the loans be secured continuously by collateral in cash, cash equivalents or U.S. Treasury bills maintained on a current basis at an amount at least equal to the market value of the securities loaned. The Fund continues to receive the equivalent of the interest or dividends paid by the issuer on the securities loaned as well as the benefit of an increase and the detriment of any decrease in the market value of the securities loaned and would also receive compensation based on investment of the collateral. The Fund would not, however, have the right to vote any securities having voting rights during the existence of the loan, but could call the loan in anticipation of an important vote to be taken among holders of the securities or of the giving or withholding of consent on a material matter affecting the investment.

As with other extensions of credit, there are risks of delay in recovery or even loss of rights in the collateral should the borrower of the securities fail financially. At no time would the value of the securities loaned exceed 33 1/3% of the value of the Fund's total assets.

PORTFOLIO TURNOVER. Although the Fund does not purchase securities with a view to rapid turnover, there are no limitations on the length of time that portfolio securities must be held. Portfolio turnover can occur for a number of reasons, including calls for redemption, general conditions in the securities markets, more favorable investment opportunities in other securities, or other factors relating to the desirability of holding or changing a portfolio investment. The portfolio turnover rates may vary greatly from year to year. A high rate of portfolio turnover in the Fund would result in increased transaction expense, which must be borne by the Fund. High portfolio turnover may also result in the realization of capital gains or losses and,

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to the extent net short-term capital gains are realized, any distributions resulting from such gains will be considered ordinary income for federal income tax purposes.

LEVERAGE

The Fund may issue preferred shares or borrow money or issue debt securities to increase its assets available for investment. The Fund currently anticipates that it will issue, as soon as practicable after the closing of this offering, cumulative preferred shares with an aggregate liquidation preference of up to approximately 33% of the Fund's total assets immediately after issuance. It is anticipated that the preferred shares will have a liquidation preference of $25,000 per share plus an amount equal to accumulated but unpaid dividends. As a non-fundamental policy, such preferred shares, borrowings or debt securities may not exceed 38% of the Fund's total assets. However, the Board of Trustees reserves the right to issue preferred shares, debt securities or borrow to the extent permitted by the 1940 Act. The Fund generally will not issue preferred shares, debt securities or borrow unless Calamos expects that the Fund will achieve a greater return on such proceeds from leverage than the additional costs the Fund incurs as a result of such leverage. The Fund also may borrow money as a temporary measure for extraordinary or emergency purposes, including the payment of dividends and the settlement of securities transactions that otherwise might require untimely dispositions of the Fund's holdings. When the Fund leverages its assets, the fees paid to Calamos for investment management services will be higher than if the Fund did not borrow because Calamos' fees are calculated based on the Fund's managed assets, which include the proceeds of the issuance of preferred shares, debt securities or any outstanding borrowings. Consequently, the Fund and Calamos may have differing interests in determining whether to leverage the Fund's assets.

The Fund's use of leverage is premised upon the expectation that the Fund's preferred share dividends or borrowing cost will be lower than the return the Fund achieves on its investments with the proceeds of the issuance of preferred shares, borrowings or debt securities. Such difference in return may result from the Fund's higher credit rating or the short-term nature of its borrowing compared to the long-term nature of its investments. Since the total assets of the Fund (including the assets obtained from leverage) may be invested in higher yielding portfolio investments or portfolio investments with the potential for capital appreciation, the holders of common shares will be the beneficiaries of any such incremental return. Should the differential between the underlying assets and cost of leverage narrow, the incremental return "pick up" will be reduced. Furthermore, if long-term interest rates rise or the Fund otherwise incurs losses on its investments, the Fund's net asset value attributable to its common shares will reflect the decline in the value of portfolio holdings resulting therefrom to a greater extent than if the Fund was not leveraged.

Leverage creates risks that may adversely affect the return for the holders of common shares, including:

- the likelihood of greater volatility of net asset value and market price of common shares;

- fluctuations in the dividend rates on any preferred shares or in interest rates on borrowings and debt securities;

- increased operating costs, which may reduce the Fund's total return; and

- the potential for a decline in the value of an investment acquired with proceeds from leverage, while the Fund's obligations under such leverage remains fixed.

To the extent the income or capital appreciation derived from securities purchased with funds received from leverage exceeds the cost of leverage, the Fund's return will be greater than if leverage had not been used. Conversely, if the income or capital appreciation from the securities purchased with such funds is not sufficient to cover the cost of leverage or if the Fund incurs capital losses, the return of the Fund will be less than if leverage had not been used, and therefore the amount available for distribution to common shareholders as dividends and other distributions will be reduced or potentially eliminated. Calamos may determine to maintain the Fund's leveraged position if it expects that the long-term benefits

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to the Fund's common shareholders of maintaining the leveraged position will outweigh the current reduced return. Capital raised through the issuance of preferred shares, borrowings or debt securities will be subject to dividend payments or interest costs that may or may not exceed the income and appreciation on the assets purchased. The issuance of preferred shares involves offering expenses and other costs and may limit the Fund's freedom to pay dividends on common shares or to engage in other activities. The Fund also may be required to maintain minimum average balances in connection with borrowings or to pay a commitment or other fee to maintain a line of credit. Either of these requirements would increase the cost of borrowing over the stated interest rate. The Fund will pay (and common shareholders will bear) any costs and expenses relating to any borrowings and issuance of debt securities and to the issuance and ongoing maintenance of preferred shares (for example, a participation fee paid at what it expects will be an annual rate of 0.25% of preferred share liquidation preference to broker-dealers successfully participating in preferred share auctions). Net asset value will be reduced immediately following any offering of preferred shares by the costs of that offering paid by the Fund.

Under the 1940 Act, the Fund is not permitted to issue preferred shares unless immediately after such issuance the net asset value of the Fund's portfolio is at least 200% of the liquidation value of the outstanding preferred shares (i.e., such liquidation value may not exceed 50% of the value of the Fund's total assets). In addition, the Fund is not permitted to declare any cash dividend or other distribution on its common shares unless, at the time of such declaration, the net asset value of the Fund's portfolio (determined after deducting the amount of such dividend or distribution) is at least 200% of such liquidation value. In the event preferred shares are issued, the Fund intends, to the extent possible, to purchase or redeem preferred shares from time to time to maintain coverage of any preferred shares of at least 200%. Under the 1940 Act, the Fund is not permitted to incur indebtedness unless immediately after such borrowing the Fund has an asset coverage of at least 300% of the aggregate outstanding principal balance of indebtedness (i.e., such indebtedness may not exceed 33 1/3% of the value of the Fund's total assets). Additionally, under the 1940 Act, the Fund may not declare any dividend or other distribution upon any class of its shares, or purchase any such shares, unless the aggregate indebtedness of the Fund has, at the time of the declaration of any such dividend or distribution or at the time of any such purchase, an asset coverage of at least 300% after deducting the amount of such dividend, distribution, or purchase price, as the case may be.

The Fund may be subject to certain restrictions on investments imposed by guidelines of one or more NRSROs that may issue ratings for the preferred shares or debt instruments issued by the Fund. These guidelines may impose asset coverage or portfolio composition requirements that are more stringent than those imposed by the 1940 Act. Certain types of borrowings may result in the Fund being subject to covenants in credit agreements, including those relating to asset coverage, borrowing base and portfolio composition requirements and additional covenants that may affect the Fund's ability to pay dividends and distributions on common shares in certain instances. The Fund may also be required to pledge its assets to the lenders in connection with certain types of borrowings. Calamos does not anticipate that these covenants or restrictions will adversely affect its ability to manage the Fund's portfolio in accordance with the Fund's investment objective and policies. Due to these covenants or restrictions, the Fund may be forced to liquidate investments at times and at prices that are not favorable to the Fund, or the Fund may be forced to forgo investments that Calamos otherwise views as favorable.

If and the extent to which the Fund employs leverage will depend on many factors, the most important of which are investment outlook, market conditions and interest rates. Successful use of a leveraging strategy depends on Calamos' ability to predict correctly interest rates and market movements. There is no assurance that a leveraging strategy will be successful during any period in which it is employed.

EFFECTS OF LEVERAGE

Assuming the Fund issues preferred shares with a liquidation preference equal to approximately 33% of the Fund's total assets and an annual dividend rate of 3.80% of such liquidation preference (which rate is approximately the current rate that Calamos expects the Fund to pay, based on market rates as of September 26, 2005), income generated by the Fund's portfolio (net of estimated expenses) would need to

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exceed 1.27% in order to cover such dividend payments on the preferred shares. Actual dividend rates may vary and may be significantly higher or lower than the rate estimated above.

The following table illustrates the hypothetical effect on the return to a holder of the Fund's common shares of the leverage obtained by issuing preferred shares with a liquidation preference equal to 33% of the Fund's total assets after issuance, assuming hypothetical annual returns of the Fund's portfolio of minus 10% to plus 10% and dividends on preferred shares at an annual dividend rate of 3.80%. As the table shows, leverage generally increases the return to common shareholders when portfolio return is positive and greater than the cost of leverage and decreases the return when the portfolio return is negative or less than the cost of leverage. The figures appearing in the table are hypothetical and actual returns may be greater or less than those appearing in the table.

Assumed Portfolio Return (Net of
  Expenses)..............................     (10)%      (5)%        0%      5%      10%
Corresponding Common Share Return........  (16.90)%   (9.40)%   (1.90)%   5.60%   13.10%

Until the Fund issues preferred shares or borrows, the Fund's common shares will not be leveraged, and the risks and special considerations related to leverage described in this prospectus will not apply. Such leveraging of the common shares cannot be fully achieved until the proceeds resulting from the use of leverage have been invested in longer term debt instruments or equity securities in accordance with the Fund's investment objective and policies.

INTEREST RATE TRANSACTIONS

In order to seek to reduce the interest rate risk inherent in the Fund's underlying investments and capital structure, the Fund, if market conditions are deemed favorable, may enter into interest rate swap or cap transactions to attempt to protect itself from increasing dividend or interest expenses on its leverage. Interest rate swaps involve the Fund's agreement with the swap counterparty to pay a fixed rate payment in exchange for the counterparty agreeing to pay the Fund a payment at a variable rate that is expected to approximate the rate of any variable rate payment obligation on the Fund's leverage. The payment obligations would be based on the notional amount of the swap.

The Fund may use an interest rate cap that would require it to pay a premium to the cap counterparty and would entitle it, to the extent that a specified variable rate index exceeds a predetermined fixed rate, to receive from the counterparty payment of the difference based on the notional amount of such cap. The Fund would use interest rate swaps or caps only with the intent to reduce or eliminate the risk that an increase in short-term interest rates could have on common share net earnings as a result of leverage.

The Fund will usually enter into swaps or caps on a net basis; that is, the two payment streams will be netted out in a cash settlement on the payment date or dates specified in the instrument, with the Fund receiving or paying, as the case may be, only the net amount of the two payments. The Fund intends to maintain in a segregated account with its custodian cash or liquid securities having a value at least equal to the Fund's net payment obligations under any swap transaction, marked-to-market daily.

The use of interest rate swaps and caps is a highly specialized activity that involves investment techniques and risks different from those associated with ordinary portfolio security transactions. Depending on the state of interest rates in general, the Fund's use of interest rate swaps or caps could enhance or harm the overall performance of the common shares. To the extent that there is a decline in interest rates for maturities equal to the remaining maturity on the Fund's fixed rate payment obligation under the interest rate swap or equal to the remaining term of the interest rate cap, the value of the swap or cap (which initially has a value of zero) could decline, and could result in a decline in the net asset value of the common shares. If, on the other hand, such rates were to increase, the value of the swap or cap could increase, and thereby increase the net asset value of the common shares. As interest rate swaps or caps approach their maturity, their positive or negative value due to interest rate changes will approach zero.

In addition, if the short-term interest rates effectively received by the Fund during the term of an interest rate swap are lower than the Fund's fixed rate of payment on the swap, the swap will increase the

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Fund's operating expenses and reduce common share net earnings. For example, if the Fund were to (A) issue preferred shares representing 33% of the Fund's total assets and (B) enter into one or more interest rate swaps in a notional amount equal to 75% of its outstanding preferred shares under which the Fund would receive a short-term swap rate that would vary based on changes in short-term interest rates, with an initial short-term rate of 3.80% and pay a fixed swap rate of 4.30% over the term of the swap, the swap would initially effectively increase Fund expenses and reduce Fund common share net earnings at an annual rate of approximately 0.19% as a percentage of net assets attributable to common shares and approximately 0.12% as a percentage of managed assets. If, on the other hand, later during the term of the swap the short-term interest rates rise so that the short-term rate effectively received by the Fund on the swap is higher than the Fund's fixed rate of payment on the interest rate swap, the swap would enhance common share net earnings. In either case, the swap would be intended to have the effect of reducing fluctuations in the Fund's cost of leverage due to changes in short-term interest rates during the term of the swap. The example above is purely for illustrative purposes and is not predictive of the actual percentage of the Fund's leverage that will be hedged by a swap, the actual fixed rates that the Fund will pay under the swap (which will depend on market interest rates for the applicable maturities at the time the Fund enters into swaps) or the actual short-term rates that the Fund will receive on any swaps (which fluctuate frequently during the term of the swap, and may change significantly from initial levels), or the actual impact such swaps will have on the Fund's expenses and common share net earnings.

Buying interest rate caps could enhance the performance of the common shares by providing a maximum leverage expense. Buying interest rate caps could also increase the operating expenses of the Fund and decrease the net earnings of the common shares in the event that the premium paid by the Fund to the counterparty exceeds the additional amount the Fund would have been required to pay on its preferred shares due to increases in short-term interest rates during the term of the cap had it not entered into the cap agreement. The Fund has no current intention of selling an interest rate cap.

Interest rate swaps and caps do not involve the delivery of securities or other underlying assets or principal. Accordingly, the risk of loss with respect to interest rate swaps is limited to the net amount of interest payments that the Fund is contractually obligated to make. If the counterparty defaults, the Fund would not be able to use the anticipated net receipts under the swap or cap to offset the dividend or interest payments on the Fund's leverage. Depending on whether the Fund would be entitled to receive net payments from the counterparty on the swap or cap, which in turn would depend on the general state of short-term interest rates at that point in time, such a default could negatively impact the performance of the common shares.

Although this will not guarantee that the counterparty does not default, the Fund will not enter into an interest rate swap or cap transaction with any counterparty that Calamos believes does not have the financial resources to honor its obligation under the interest rate swap or cap transaction. Further, Calamos will continually monitor the financial stability of a counterparty to an interest rate swap or cap transaction in an effort to proactively protect the Fund's investments.

In addition, at the time the interest rate swap or cap transaction reaches its scheduled termination date, there is a risk that the Fund will not be able to obtain a replacement transaction or that the terms of the replacement will not be as favorable as on the expiring transaction. If this occurs, it could have a negative impact on the performance of the common shares.

The Fund may choose or be required to redeem some or all preferred shares or prepay any borrowings. This redemption or prepayment would likely result in the Fund seeking to terminate early all or a portion of any swap or cap transaction. Such early termination of a swap could result in a termination payment by or to the Fund. An early termination of a cap could result in a termination payment to the Fund.

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RISK FACTORS

GENERAL. The Fund is a newly organized, diversified, closed-end management investment company designed primarily as a long-term investment and not as a trading tool. The Fund invests in a diversified portfolio of common and preferred stocks, convertible securities and income producing securities such as investment grade and below investment grade debt securities. An investment in the Fund's common shares may be speculative and it involves a high degree of risk. The Fund should not constitute a complete investment program. Due to the uncertainty in all investments, there can be no assurance that the Fund will achieve its investment objective.

NO OPERATING HISTORY. The Fund has no operating history or history of public trading.

MARKET PRICE OF SHARES. Shares of closed-end funds frequently trade at a market price that is below their net asset value. This is commonly referred to as "trading at a discount." This characteristic of shares of closed-end funds is a risk separate and distinct from the risk that the Fund's net asset value may decrease. Investors who sell their shares within a relatively short period after completion of the public offering are likely to be exposed to this risk. Accordingly, the Fund is designed primarily for long-term investors and should not be considered a vehicle for trading purposes. Net asset value will be reduced following the offering by the sales load and the amount of organizational and offering expenses paid by the Fund and immediately following any offering of preferred shares by the costs of that offering paid by the Fund.

Whether investors will realize a gain or loss upon the sale of the Fund's common shares will depend upon whether the market value of the shares at the time of sale is above or below the price the investor paid, taking into account transaction costs, for the shares and is not directly dependent upon the Fund's net asset value. Because the market value of the Fund's shares will be determined by factors such as the relative demand for and supply of the shares in the market, general market conditions and other factors beyond the control of the Fund, the Fund cannot predict whether its common shares will trade at, below or above net asset value, or below or above the initial offering price for the shares.

EQUITY SECURITIES. Equity investments are subject to greater fluctuations in market value than other asset classes as a result of such factors as the issuer's business performance, investor perceptions, stock market trends and general economic conditions. Equity securities are subordinated to bonds and other debt instruments in a company's capital structure in terms of priority to corporate income and liquidation payments. The Fund may invest in preferred stocks and convertible securities of any rating, including below investment grade.

HIGH YIELD SECURITIES. The Fund may invest in high yield securities of any rating. Investment in high yield securities involves substantial risk of loss. Below investment grade non-convertible debt securities or comparable unrated securities are commonly referred to as "junk bonds" and are considered predominantly speculative with respect to the issuer's ability to pay interest and principal and are susceptible to default or decline in market value due to adverse economic and business developments. The market values for high yield securities tend to be very volatile, and these securities are less liquid than investment grade debt securities. For these reasons, your investment in the Fund is subject to the following specific risks:

- increased price sensitivity to changing interest rates and to a deteriorating economic environment;

- greater risk of loss due to default or declining credit quality;

- adverse company specific events are more likely to render the issuer unable to make interest and/or principal payments; and

- if a negative perception of the high yield market develops, the price and liquidity of high yield securities may be depressed. This negative perception could last for a significant period of time.

Adverse changes in economic conditions are more likely to lead to a weakened capacity of a high yield issuer to make principal payments and interest payments than an investment grade issuer. The principal amount of high yield securities outstanding has proliferated in the past decade as an increasing number of issuers have used high yield securities for corporate financing. An economic downturn could severely affect

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the ability of highly leveraged issuers to service their debt obligations or to repay their obligations upon maturity. Similarly, downturns in profitability in specific industries could adversely affect the ability of high yield issuers in those industries to meet their obligations. The market values of lower quality debt securities tend to reflect individual developments of the issuer to a greater extent than do higher quality securities, which react primarily to fluctuations in the general level of interest rates. Factors having an adverse impact on the market value of lower quality securities may have an adverse effect on the Fund's net asset value and the market value of its common shares. In addition, the Fund may incur additional expenses to the extent it is required to seek recovery upon a default in payment of principal or interest on its portfolio holdings. In certain circumstances, the Fund may be required to foreclose on an issuer's assets and take possession of its property or operations. In such circumstances, the Fund would incur additional costs in disposing of such assets and potential liabilities from operating any business acquired.

The secondary market for high yield securities may not be as liquid as the secondary market for more highly rated securities, a factor that may have an adverse effect on the Fund's ability to dispose of a particular security. There are fewer dealers in the market for high yield securities than for investment grade obligations. The prices quoted by different dealers may vary significantly and the spread between the bid and asked price is generally much larger than for higher quality instruments. Under adverse market or economic conditions, the secondary market for high yield securities could contract further, independent of any specific adverse changes in the condition of a particular issuer, and these instruments may become illiquid. As a result, the Fund could find it more difficult to sell these securities or may be able to sell the securities only at prices lower than if such securities were widely traded. Prices realized upon the sale of such lower rated or unrated securities, under these circumstances, may be less than the prices used in calculating the Fund's net asset value.

Since investors generally perceive that there are greater risks associated with lower quality debt securities of the type in which the Fund may invest a portion of its assets, the yields and prices of such securities may tend to fluctuate more than those for higher rated securities. In the lower quality segments of the debt securities market, changes in perceptions of issuers' creditworthiness tend to occur more frequently and in a more pronounced manner than do changes in higher quality segments of the debt securities market, resulting in greater yield and price volatility.

Securities rated below investment grade are speculative with respect to the capacity to pay interest and repay principal in accordance with the terms of such securities. A rating of C from Moody's means that the issue so rated can be regarded as having extremely poor prospects of ever attaining any real investment standing. Standard & Poor's assigns a rating of C to issues that are currently highly vulnerable to nonpayment, and the C rating may be used to cover a situation in which a bankruptcy petition has been filed or similar action taken, but payments on the obligation are being continued (a C rating is also assigned to a preferred stock issue in arrears on dividends or sinking fund payments, but that is currently paying). See the statement of additional information for a description of Moody's and Standard & Poor's ratings.

If the Fund invests in high yield securities that are rated C or below, the Fund will incur significant risk in addition to the risks associated with investments in high yield securities discussed above. Distressed securities frequently do not produce income while they are outstanding. The Fund may purchase distressed securities that are in default or the issuers of which are in bankruptcy. The Fund may be required to bear certain extraordinary expenses in order to protect and recover its investment. The Fund also will be subject to significant uncertainty as to when and in what manner and for what value the obligations evidenced by the distressed securities will eventually be satisfied.

FOREIGN SECURITIES. Investments in non-U.S. issuers may involve unique risks compared to investing in securities of U.S. issuers. These risks are more pronounced to the extent that the Fund invests a significant portion of its non-U.S. investments in one region or in the securities of emerging market issuers. These risks may include:

- less information about non-U.S. issuers or markets may be available due to less rigorous disclosure or accounting standards or regulatory practices;

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- many non-U.S. markets are smaller, less liquid and more volatile and therefore, in a changing market, Calamos may not be able to sell the Fund's portfolio securities at times, in amounts and at prices it considers reasonable;

- the economies of non-U.S. countries may grow at slower rates than expected or may experience a downturn or recession;

- economic, political and social developments may adversely affect the securities markets, including expropriation and nationalization;

- the difficulty in obtaining or enforcing a court judgment in non-U.S. countries;

- restrictions on foreign investments in non-U.S. jurisdictions;

- difficulties in effecting the repatriation of capital invested in non-U.S. countries;

- withholding and other non-U.S. taxes may decrease the Fund's return; and

- dividend income the Fund receives from foreign securities may not be eligible for the special tax treatment applicable to qualified dividend income.

There may be less publicly available information about non-U.S. markets and issuers than is available with respect to U.S. securities and issuers. Non-U.S. companies generally are not subject to accounting, auditing and financial reporting standards, practices and requirements comparable to those applicable to U.S. companies. The trading markets for most non-U.S. securities are generally less liquid and subject to greater price volatility than the markets for comparable securities in the United States. The markets for securities in certain emerging markets are in the earliest stages of their development. Even the markets for relatively widely traded securities in certain non-U.S. markets, including emerging market countries, may not be able to absorb, without price disruptions, a significant increase in trading volume or trades of a size customarily undertaken by institutional investors in the United States.

Additionally, market making and arbitrage activities are generally less extensive in such markets, which may contribute to increased volatility and reduced liquidity.

Economies and social and political conditions in individual countries may differ unfavorably from the United States. Non-U.S. economies may have less favorable rates of growth of gross domestic product, rates of inflation, currency valuation, capital reinvestment, resource self-sufficiency and balance of payments positions. Many countries have experienced substantial, and in some cases extremely high, rates of inflation for many years. Inflation and rapid fluctuations in inflation rates have had, and may continue to have, very negative effects on the economies and securities markets of certain emerging market countries. Unanticipated political or social developments may also affect the values of the Fund's investments and the availability to the Fund of additional investments in such countries.

CURRENCY RISK. The value of the securities denominated or quoted in foreign currencies may be adversely affected by fluctuations in the relative currency exchange rates and by exchange control regulations. The Fund's investment performance may be negatively affected by a devaluation of a currency in which the Fund's investments are denominated or quoted. Further, the Fund's investment performance may be significantly affected, either positively or negatively, by currency exchange rates because the U.S. dollar value of securities denominated or quoted in another currency will increase or decrease in response to changes in the value of such currency in relation to the U.S. dollar.

INTEREST RATE RISK. Fixed income securities, including high yield securities, are subject to certain common risks, including the following:

- If interest rates go up, the value of debt securities in the Fund's portfolio generally will decline.

- During periods of declining interest rates, the issuer of a security may exercise its option to prepay principal earlier than scheduled, forcing the Fund to reinvest in lower yielding securities. This is known as call or prepayment risk. Debt securities frequently have call features that allow the issuer to repurchase the security prior to its stated maturity. An issuer may redeem an obligation if the

30

issuer can refinance the debt at a lower cost due to declining interest rates or an improvement in the credit standing of the issuer.

- During periods of rising interest rates, the average life of certain types of securities may be extended because of slower than expected principal payments. This may lock in a below market interest rate, increase the security's duration (the estimated period until the security is paid in full) and reduce the value of the security. This is known as extension risk.

- Rising interest rates could result in an increase in the cost of the Funds' leverage and could adversely affect the ability of the Fund to meet asset coverage requirements with respect to leverage.

DEFAULT RISK. Default risk refers to the risk that a company that issues a debt security will be unable to fulfill its obligations to repay principal and interest. The lower a debt security is rated, the greater its default risk.

ILLIQUID INVESTMENTS. The Fund may invest up to 15% of its managed assets in securities that, at the time of investment, are illiquid (determined using the Commission's standard applicable to investment companies, i.e., securities that can not be disposed of within 7 days in the ordinary course of business at approximately the value at which the Fund has valued the securities). The Fund may also invest without limit in Rule 144A Securities. Calamos, under the supervision of the Board of Trustees, will determine whether securities purchased under Rule 144A are illiquid (that is, not readily marketable) and thus subject to the Fund's limit on investing no more than 15% of its managed assets in illiquid securities. Investments in Rule 144A Securities could have the effect of increasing the amount of the Fund's assets invested in illiquid securities if qualified institutional buyers are unwilling to purchase these Rule 144A Securities. Illiquid securities may be difficult to dispose of at a fair price at the times when the Fund believes it is desirable to do so. Investment of the Fund's assets in illiquid securities may restrict the Fund's ability to take advantage of market opportunities. The market price of illiquid securities generally is more volatile than that of more liquid securities, which may adversely affect the price that the Fund pays for or recovers upon the sale of illiquid securities. Illiquid securities are also more difficult to value and Calamos' judgment may play a greater role in the valuation process. The risks associated with illiquid securities may be particularly acute in situations in which the Fund's operations require cash and could result in the Fund borrowing to meet its short-term needs or incurring losses on the sale of illiquid securities.

CONVERTIBLE SECURITIES. Convertible securities generally offer lower interest or dividend yields than non-convertible securities of similar quality. The market values of convertible securities tend to decline as interest rates increase and, conversely, to increase as interest rates decline. However, the convertible security's market value tends to reflect the market price of the common stock of the issuing company when that stock price is greater than the convertible security's "conversion price." The conversion price is defined as the predetermined price at which the convertible security could be exchanged for the associated stock. As the market price of the underlying common stock declines, the price of the convertible security tends to be influenced more by the yield of the convertible security. Thus, it may not decline in price to the same extent as the underlying common stock. In the event of a liquidation of the issuing company, holders of convertible securities would be paid before the company's common stockholders. Consequently, the issuer's convertible securities generally entail less risk than its common stock.

SYNTHETIC CONVERTIBLE INSTRUMENTS. The value of a synthetic convertible instrument may respond differently to market fluctuations than a convertible security because a synthetic convertible instrument is composed of two or more separate securities, each with its own market value. In addition, if the value of the underlying common stock or the level of the index involved in the convertible component falls below the exercise price of the warrant or option, the warrant or option may lose all value. Synthetic convertible instruments created by other parties have the same attributes of a convertible security, however, the issuer of the synthetic convertible instrument assumes the credit risk associated with the investment, rather than the issuer of the underlying equity security into which the instrument is convertible. Therefore, the Fund is subject to the credit risk associated with the party creating the synthetic convertible instrument.

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RISKS ASSOCIATED WITH OPTIONS. There are several risks associated with transactions in options. For example, there are significant differences between the securities and options markets that could result in an imperfect correlation among these markets, causing a given transaction not to achieve its objectives. A decision as to whether, when and how to use options involves the exercise of skill and judgment, and even a well-conceived transaction may be unsuccessful to some degree because of market behavior or unexpected events. The ability of the Fund to utilize options successfully will depend on Calamos' ability to predict pertinent market movements, which cannot be assured.

The Fund's ability to close out its position as a purchaser or seller of an OCC or exchange listed put or call option is dependent, in part, upon the liquidity of the option market. Among the possible reasons for the absence of a liquid option market are: (i) insufficient trading interest in certain options;
(ii) restrictions on transactions imposed by an exchange; (iii) trading halts, suspensions or other restrictions imposed with respect to particular classes or series of options or underlying securities, including reaching daily price limits; (iv) interruption of the normal operations of the OCC or an exchange;
(v) inadequacy of the facilities of an exchange or OCC to handle current trading volume; or (vi) a decision by one or more exchanges to discontinue the trading of options (or a particular class or series of options), in which event the relevant market for that option on that exchange would cease to exist, although outstanding options on that exchange would generally continue to be exercisable in accordance with their terms. If the Fund were unable to close out an option that it has purchased on a security, it would have to exercise the option in order to realize any profit or the option would expire and become worthless. If the Fund were unable to close out a covered call option that it had written on a security, it would not be able to sell the underlying security until the option expired. As the writer of a covered call option on a security, the Fund foregoes, during the option's life, the opportunity to profit from increases in the market value of the security covering the call option above the sum of the premium and the exercise price of the call.

The hours of trading for listed options may not coincide with the hours during which the underlying financial instruments are traded. To the extent that the option markets close before the markets for the underlying financial instruments, significant price and rate movements can take place in the underlying markets that cannot be reflected in the option markets until the next trading day.

Unless the parties provide for it, there is no central clearing or guaranty function in an OTC option. As a result, if the counterparty fails to make or take delivery of the security or other instrument underlying an OTC option it has entered into with the Fund or fails to make a cash settlement payment due in accordance with the terms of that option, the Fund will lose any premium it paid for the option as well as any anticipated benefit of the transaction. Accordingly, Calamos must assess the creditworthiness of each such counterparty or any guarantor or credit enhancement of the counterparty's credit to determine the likelihood that the terms of the OTC option will be satisfied. The Fund will engage in OTC option transactions only with U.S. government securities dealers recognized by the Federal Reserve Bank of New York as "primary dealers" or broker/dealers, domestic or foreign banks or other financial institutions that have received (or the guarantors of the obligation of which have received) a short-term credit rating of A-1 from S&P or P-1 from Moody's or an equivalent rating from any NRSRO or, in the case of OTC currency transactions, are determined to be of equivalent credit quality by Calamos.

The Fund may sell options on individual securities and securities indices. All calls sold by the Fund must be "covered." Even though the Fund will receive the option premium to help protect it against loss, a call option sold by the Fund exposes the Fund during the term of the option to possible loss of opportunity to realize appreciation in the market price of the underlying security or instrument in excess of the exercise or strike price and may require the Fund to hold a security or instrument that it might otherwise have sold. The Fund may purchase and sell put options on individual securities and securities indices. In selling put options, there is a risk that the Fund may be required to buy the underlying security at a disadvantageous price above the market price.

LEVERAGE. The Fund may issue preferred shares, borrow money or issue debt securities. The Fund currently anticipates that it will issue cumulative preferred shares, as soon as practicable after the closing

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of this offering, with an aggregate liquidation preference of up to approximately 33% of the Fund's total assets immediately after issuance. As a non-fundamental policy, such preferred shares, borrowings or debt securities may not exceed 38% of the Fund's total assets. However, the Board of Trustees reserves the right to issue preferred shares or debt securities or borrow to the extent permitted by the 1940 Act.

Leverage creates risks that may adversely affect the return for the holders of, and distributions on, common shares, including:

- the likelihood of greater volatility of net asset value and market price of common shares;

- fluctuations in the dividend rates on any preferred shares or in interest rates on borrowings and debt securities;

- increased operating costs, which are effectively borne by common shareholders, and may reduce the Fund's total return; and

- the potential for a decline in the value of an investment acquired with proceeds from leverage, while the Fund's obligations under such leverage remain fixed.

The Fund's use of leverage is premised upon the expectation that the Fund's preferred share dividends or borrowing cost will be lower than the return the Fund achieves on its investments with the proceeds of leverage. Such difference in return may result from the Fund's higher credit rating or the short-term nature of its borrowing compared to the long-term nature of its investments. Since the total assets of the Fund (including the assets obtained from leverage) will be invested in the higher yielding portfolio investments or portfolio investments with the potential for capital appreciation, the holders of common shares will be the beneficiaries of the incremental return. Should the differential between the underlying assets and cost of leverage narrow, the incremental return "pick up" will be reduced. Furthermore, if long-term interest rates rise or the Fund otherwise incurs losses on its investments, the Fund's net asset value attributable to its common shares will reflect the decline in the value of portfolio holdings resulting therefrom to a greater extent than if the Fund was not leveraged.

To the extent the income or capital appreciation derived from securities purchased with funds received from leverage exceeds the cost of leverage, the Fund's return will be greater than if leverage had not been used. Conversely, if the income or capital appreciation from the securities purchased with such funds is not sufficient to cover the cost of leverage or if the Fund incurs capital losses, the return of the Fund will be less than if leverage had not been used, and therefore the amount available for distribution to common shareholders as dividends and other distributions will be reduced or potentially eliminated. Common shareholders bear the cost of any leverage.

Certain types of borrowings may result in the Fund being subject to covenants in credit agreements, including those relating to asset coverage, borrowing base and portfolio composition requirements and additional covenants that may affect the Fund's ability to pay dividends and distributions on common shares in certain instances. The Fund may also be required to pledge its assets to the lenders in connection with certain types of borrowings. The Fund may be subject to certain restrictions on investments imposed by guidelines of one or more NRSRO that may issue ratings for the preferred shares or short-term debt instruments issued by the Fund. These guidelines may impose asset coverage or portfolio composition requirements that are more stringent than those imposed by the 1940 Act.

If the Fund's ability to make distributions on its common shares is limited, such limitation could, under certain circumstances, impair the ability of the Fund to maintain its qualification for taxation as a regulated investment company, which would have adverse federal income tax consequences for shareholders. To the extent that the Fund is required, in connection with maintaining 1940 Act asset coverage requirements or otherwise, or elects to redeem any preferred shares or prepay any borrowings, the Fund may need to liquidate investments to fund such redemptions or prepayments. Liquidation at times of adverse economic conditions may result in capital loss and reduce returns to common shareholders.

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Since Calamos' investment management fee is a percentage of the Fund's managed assets, Calamos' fee will be higher if the Fund is leveraged and Calamos will have an incentive to be more aggressive and leverage the Fund.

INTEREST RATE TRANSACTIONS RISK. The Fund may enter into an interest rate swap or cap transaction to attempt to protect itself from increasing dividend or interest expenses on its preferred shares, debt securities or other borrowings resulting from increasing short-term interest rates. A decline in interest rates may result in a decline in the value of the swap or cap, which may result in a decline in the net asset value of the Fund.

Depending on the state of interest rates in general, the Fund's use of interest rate swap or cap transactions could enhance or harm the overall performance of the common shares. To the extent there is a decline in interest rates, the value of the interest rate swap or cap could decline, and could result in a decline in the net asset value of the common shares. In addition, if the counterparty to an interest rate swap or cap defaults, the Fund would not be able to use the anticipated net receipts under the swap or cap to offset the dividend or interest payments on the Fund's leverage.

Depending on whether the Fund would be entitled to receive net payments from the counterparty on the swap or cap, which in turn would depend on the general state of short-term interest rates at that point in time, such a default could negatively impact the performance of the common shares. In addition, at the time an interest rate swap or cap transaction reaches its scheduled termination date, there is a risk that the Fund would not be able to obtain a replacement transaction or that the terms of the replacement would not be as favorable as on the expiring transaction. If either of these events occurs, it could have a negative impact on the performance of the common shares.

If the Fund fails to maintain a required 200% asset coverage of the liquidation value of the outstanding preferred shares or if the Fund loses its expected rating on its preferred shares or fails to maintain other covenants with respect to its preferred shares, the Fund may be required to redeem some or all of the preferred shares. Similarly, the Fund could be required to prepay the principal amount of any debt securities or other borrowings. Such redemption or prepayment would likely result in the Fund seeking to terminate early all or a portion of any swap or cap transaction. Early termination of a swap could result in a termination payment by or to the Fund. Early termination of a cap could result in a termination payment to the Fund. The Fund intends to maintain in a segregated account with its custodian cash or liquid securities having a value at least equal to the Fund's net payment obligations under any swap transaction, marked-to-market daily.

TAX RISK. The Fund may invest in certain securities, such as certain convertible and high yield securities, for which the federal income tax treatment may not be clear or may be subject to recharacterization by the IRS. It could be more difficult for the Fund to comply with certain tax requirements applicable to regulated investment companies if the tax characterization of the Fund's investments is uncertain or if the tax treatment of the income from such investments were successfully challenged by the IRS. See "U.S. Federal Income Tax Matters."

Certain of the Fund's investment practices are subject to special and complex federal income tax provisions that may, among other things, (i) disallow, suspend or otherwise limit the allowance of certain losses or deductions, (ii) convert tax-advantaged, long-term capital gains and qualified dividend income into higher taxed short-term capital gain or ordinary income,
(iii) convert an ordinary loss or a deduction into a capital loss (the deductibility of which is more limited), (iv) cause the Fund to recognize income or gain without a corresponding receipt of cash, (v) adversely affect the timing as to when a purchase or sale of stock or securities is deemed to occur, and
(vi) adversely alter the characterization of certain complex financial transactions. The Fund will monitor its transactions and may make certain tax elections where applicable in order to mitigate the effect of these provisions, if possible.

MANAGEMENT RISK. Calamos' judgment about the attractiveness, relative value or potential appreciation of a particular sector, security or investment strategy may prove to be incorrect.

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ANTITAKEOVER PROVISIONS. The Fund's Agreement and Declaration of Trust and By-Laws include provisions that could limit the ability of other entities or persons to acquire control of the Fund or to change the composition of its Board of Trustees. Such provisions could limit the ability of shareholders to sell their shares at a premium over prevailing market prices by discouraging a third party from seeking to obtain control of the Fund. These provisions include staggered terms of office for the Trustees, advance notice requirements for shareholder proposals, and super-majority voting requirements for certain transactions with affiliates, converting the Fund to an open-end investment company or a merger, asset sale or similar transaction. Holders of preferred shares will have voting rights in addition to and separate from the voting rights of common shareholders with respect to certain of these matters. See "Description of Shares -- Preferred Shares" and "Certain Provisions of the Agreement and Declaration of Trust and By-Laws." The holders of preferred shares, on the one hand, and the holders of the common shares, on the other, may have interests that conflict in these situations.

MARKET DISRUPTION RISK. Certain events have a disruptive effect on the securities markets, such as terrorist attacks (including the terrorist attacks in the United States on September 11, 2001), war and other geopolitical events, earthquakes, storms and other disasters. The Fund cannot predict the effects of similar events in the future on the markets or economy of the U.S. or other countries.

MANAGEMENT OF THE FUND

TRUSTEES AND OFFICERS

The Fund's Board of Trustees provides broad supervision over the affairs of the Fund. The officers of the Fund are responsible for the Fund's operations. Currently, there are seven Trustees of the Fund, three of whom are "interested persons" of the Fund (as defined in the 1940 Act) and four of whom are not "interested persons." The names and business addresses of the trustees and officers of the Fund and their principal occupations and other affiliations during the past five years are set forth under "Management of the Fund" in the statement of additional information.

INVESTMENT ADVISER

The Fund's investments are managed by Calamos, 2020 Calamos Court, Naperville, IL. On August 31, 2005 Calamos managed approximately $41 billion in assets of individuals and institutions. Calamos is an indirect subsidiary of Calamos Asset Management, Inc., whose voting shares are majority-owned by Calamos Family Partners, Inc., which is controlled by John P. Calamos, Sr. and the Calamos family. Calamos Asset Management, Inc. is publicly traded on the NASDAQ exchange under the ticker symbol "CLMS".

INVESTMENT MANAGEMENT AGREEMENT

Subject to the overall authority of the Board of Trustees, Calamos regularly provides the Fund with investment research, advice and supervision and furnishes continuously an investment program for the Fund. In addition, Calamos furnishes for use of the Fund such office space and facilities as the Fund may require for its reasonable needs, supervises the Fund's business and affairs and provides the following other services on behalf of the Fund and not provided by persons not a party to the investment management agreement: (a) preparing or assisting in the preparation of reports to and meeting materials for the Trustees; (b) supervising, negotiating contractual arrangements with, to the extent appropriate, and monitoring the performance of, accounting agents, custodians, depositories, transfer agents and pricing agents, accountants, attorneys, printers, underwriters, brokers and dealers, insurers and other persons in any capacity deemed to be necessary or desirable to Fund operations;
(c) assisting in the preparation and making of filings with the Commission and other regulatory and self-regulatory organizations, including, but not limited to, preliminary and definitive proxy materials, amendments to the Fund's registration statement on Form N-2 and semi-annual reports on Form N-SAR and Form N-CSR; (d) overseeing the tabulation of proxies by the Fund's transfer agent; (e) assisting in the preparation and filing of the Fund's federal, state and local tax returns; (f) assisting in the preparation and filing of the Fund's federal excise

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tax return pursuant to Section 4982 of the Code; (g) providing assistance with investor and public relations matters; (h) monitoring the valuation of portfolio securities and the calculation of net asset value; (i) monitoring the registration of shares of beneficial interest of the Fund under applicable federal and state securities laws; (j) maintaining or causing to be maintained for the Fund all books, records and reports and any other information required under the 1940 Act, to the extent that such books, records and reports and other information are not maintained by the Fund's custodian or other agents of the Fund; (k) assisting in establishing the accounting policies of the Fund; (l) assisting in the resolution of accounting issues that may arise with respect to the Fund's operations and consulting with the Fund's independent accountants, legal counsel and the Fund's other agents as necessary in connection therewith;
(m) reviewing the Fund's bills; (n) assisting the Fund in determining the amount of dividends and distributions available to be paid by the Fund to its shareholders, preparing and arranging for the printing of dividend notices to shareholders, and providing the transfer and dividend paying agent, the custodian, and the accounting agent with such information as is required for such parties to effect the payment of dividends and distributions; and (o) otherwise assisting the Fund as it may reasonably request in the conduct of the Fund's business, subject to the direction and control of the Trustees.

Under the investment management agreement, the Fund will pay to Calamos a fee based on the average weekly managed assets that is computed weekly and paid on a monthly basis. The fee paid by the Fund is at the annual rate of 1.00% of managed assets. Because the fees paid to Calamos are determined on the basis of the Fund's managed assets, Calamos' interest in determining whether to leverage the Fund may conflict with the interests of the Fund and its common shareholders. The Board of Trustees must approve the issuance of debt securities and/or preferred shares of the Fund.

Under the terms of its investment management agreement, except for the services and facilities provided by Calamos as set forth therein, the Fund shall assume and pay all expenses for all other Fund operations and activities and shall reimburse Calamos for any such expenses incurred by Calamos. The expenses borne by the Fund shall include, without limitation: (a) organization expenses of the Fund (including out-of-pocket expenses, but not including Calamos' overhead or employee costs); (b) fees payable to Calamos; (c) legal expenses;
(d) auditing and accounting expenses; (e) maintenance of books and records that are required to be maintained by the Fund's custodian or other agents of the Fund; (f) telephone, telex, facsimile, postage and other communications expenses; (g) taxes and governmental fees; (h) fees, dues and expenses incurred by the Fund in connection with membership in investment company trade organizations and the expense of attendance at professional meetings of such organizations; (i) fees and expenses of accounting agents, custodians, subcustodians, transfer agents, dividend disbursing agents and registrars; (j) payment for portfolio pricing or valuation services to pricing agents, accountants, bankers and other specialists, if any; (k) expenses of preparing share certificates; (l) expenses in connection with the issuance, offering, distribution, sale, redemption or repurchase of securities issued by the Fund;
(m) expenses relating to investor and public relations provided by parties other than Calamos; (n) expenses and fees of registering or qualifying shares of beneficial interest of the Fund for sale; (o) interest charges, bond premiums and other insurance expenses; (p) freight, insurance and other charges in connection with the shipment of the Fund's portfolio securities; (q) the compensation and all expenses (specifically including travel expenses relating to Fund business) of Trustees, officers and employees of the Fund who are not affiliated persons of Calamos; (r) brokerage commissions or other costs of acquiring or disposing of any portfolio securities of the Fund; (s) expenses of printing and distributing reports, notices and dividends to shareholders; (t) expenses of preparing and setting in type, printing and mailing prospectuses and statements of additional information of the Fund and supplements thereto; (u) costs of stationery; (v) any litigation expenses; (w) indemnification of Trustees and officers of the Fund; (x) costs of shareholders' and other meetings; (y) interest on borrowed money, if any; and (z) the fees and other expenses of listing the Fund's shares on the New York Stock Exchange or any other national stock exchange.

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PORTFOLIO MANAGER

John P. Calamos, Sr., Nick P. Calamos and John P. Calamos, Jr. are responsible for managing the Fund's portfolio. During the past five years, John P. Calamos, Sr. has been a Chairman, CEO and Co-Chief Investment Officer of Calamos; Nick P. Calamos has been a Senior Executive Vice President and Co-Chief Investment Officer of Calamos; and John P. Calamos, Jr. has been an Executive Vice President of Calamos. For over 20 years, the Calamos management team has managed money for their clients in convertible, high yield and global strategies. Furthermore, Calamos has extensive experience investing in foreign markets through its convertible securities and high yield securities strategies. Such experience has included investments in established as well as emerging foreign markets.

The Fund's statement of additional information provides additional information about the portfolio managers, including other accounts they manage, their ownership of the Fund and their compensation.

FUND ACCOUNTING

Under the arrangements with State Street to provide fund accounting services, State Street provides certain administrative and accounting services to the Fund and such other funds advised by Calamos that may be part of those arrangements (the Fund and such other funds are collectively referred to as the "Calamos Funds") as described more fully in the statement of additional information. For the services rendered to the Calamos Funds, State Street receives fees based on the combined managed assets of the Calamos Funds ("Combined Assets"). Each fund of the Calamos Funds pays its pro-rata share of the fees payable to State Street described below based on relative managed assets of each fund. State Street receives a fee at the annual rate of .0175% for the first $1.5 billion of Combined Assets, .0150% for the next $1.5 billion of Combined Assets, .0125% for the next $1.5 billion of Combined Assets, .010% for the next $1.5 billion of Combined Assets, .0075% for the next $1.5 billion of Combined Assets and .00375% for the Combined Assets in excess of $7.5 billion.

In addition, Calamos will also provide certain other financial accounting services to the Calamos Funds described more fully in the statement of additional information. For providing those services, Calamos will receive a fee at the annual rate of .0175% on the first $1 billion of Combined Assets; .0150% on the next $1 billion of Combined Assets; and .0110% on Combined Assets above $2 billion ("financial accounting service fee"). Each fund of the Calamos Funds will pay its pro-rata share of the financial accounting service fee to Calamos based on relative managed assets of each fund.

DIVIDENDS AND DISTRIBUTIONS;
AUTOMATIC DIVIDEND REINVESTMENT PLAN

DIVIDENDS AND DISTRIBUTIONS

The Fund intends to distribute to common shareholders all or a portion of its net investment income monthly and net realized capital gains, if any, at least annually. The first distribution is expected to be declared approximately 60 days and paid approximately 90 days after the completion of this offering, depending on market conditions.

The Fund currently intends to make monthly distributions to common shareholders at a level rate established by the Board of Trustees. The rate may be modified by the Board of Trustees from time to time. Monthly distributions may include net investment income, net realized short-term capital gain and, if necessary, return of capital. Net realized short-term capital gains distributed to common shareholders will be taxed as ordinary income. In addition, one distribution per calendar year may include net realized long-term capital gains. There is no guarantee that the Fund will realize capital gains in any given year. Pursuant to the requirements of the 1940 Act and other applicable laws, a notice would accompany each monthly distribution with respect to the estimated source of the distribution made. Distributions are subject to re-characterization for federal income tax purposes after the end of the fiscal year. The Fund may at times in its discretion pay out less than the entire amount of net investment income earned in any particular period and may at times pay out such accumulated undistributed income in addition to net investment income earned in other periods in order to permit the Fund to maintain its level distribution policy. As a result, the dividend paid by the Fund to holders of common shares for any particular period

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may be more or less than the amount of net investment income earned by the Fund during such period. In addition, in order to make such distributions, the Fund might have to sell a portion of its investment portfolio at a time when independent investment judgment might not dictate such action.

For U.S. federal income tax purposes, the Fund is required to distribute substantially all of its net investment income and net realized gains each year to both reduce its federal income tax liability and to avoid a potential excise tax. Accordingly, the Fund intends to distribute all or substantially all of its net investment income and all net realized capital gains, if any. Therefore, the Fund's final distribution for each calendar year would include any remaining net investment income and net realized capital gains, if any, undistributed during the year.

If, for any calendar year, the Fund's total distributions exceeded net investment income and net realized capital gains (the "Excess"), the Excess, distributed from the Fund's assets, would generally be treated as dividend income to the extent of the Fund's current and accumulated earnings and profits. Thereafter, such Excess would be treated as a tax-free return of capital up to the amount of the common shareholder's tax basis in his, her or its common shares, with any amounts exceeding such basis treated as gain from the sale of common shares. See "U.S. Federal Income Tax Matters."

In the event the Fund distributed the Excess, such distribution would decrease the Fund's total assets and, therefore, have the likely effect of increasing the Fund's expense ratio. There is a risk that the Fund would not eventually realize capital gains in an amount corresponding to a distribution of the Excess.

In January 2004, Calamos, on behalf of itself and certain funds, filed an exemptive application with the Commission seeking an order under the 1940 Act permitting those funds to make periodic distributions of long-term capital gains. The application may be amended to include the Fund as a party. There is no guarantee that the Fund will receive such exemptive order. The staff of the Commission has indicated that it has suspended the processing of exemptive applications requesting the type of relief referenced above, pending review by the staff of the results of an industry-wide inspection focusing on the dividend practices of closed-end investment companies. There can be no assurance as to when that review might be completed or whether, following that review, the staff would process such applications or grant such relief.

Under the 1940 Act, the Fund is not permitted to incur indebtedness unless immediately after such incurrence the Fund has an asset coverage of at least 300% of the aggregate outstanding principal balance of indebtedness. Additionally, under the 1940 Act, the Fund may not declare any dividend or other distribution upon any class of its capital shares, or purchase any such capital shares, unless the aggregate indebtedness of the Fund has, at the time of the declaration of any such dividend or distribution or at the time of any such purchase, an asset coverage of at least 300% after deducting the amount of such dividend, distribution, or purchase price, as the case may be.

While any preferred shares are outstanding, the Fund may not declare any cash dividend or other distribution on its common shares, unless at the time of such declaration, (1) all accumulated preferred dividends have been paid and (2) the net asset value of the Fund's portfolio (determined after deducting the amount of such dividend or other distribution) is at least 200% of the liquidation value of the outstanding preferred shares (expected to be equal to the original purchase price per share plus any accumulated and unpaid dividends thereon).

In addition to the limitations imposed by the 1940 Act described above, certain lenders may impose additional restrictions on the payment of dividends or distributions on the common shares in the event of a default on the Fund's borrowings. If the Fund's ability to make distributions on its common shares is limited, such limitation could, under certain circumstances, impair the ability of the Fund to maintain its qualification for taxation as a regulated investment company, which would have adverse tax consequences for the Fund and its shareholders. See "Leverage" and "U.S. Federal Income Tax Matters."

See "-- Automatic Dividend Reinvestment Plan" for information concerning the manner in which dividends and distributions to common shareholders may be automatically reinvested in common shares. Dividends and distributions may be taxable to shareholders whether they are reinvested in shares of the Fund or received in cash.

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The yield on the Fund's common shares will vary from period to period depending on factors including, but not limited to, market conditions, the timing of the Fund's investment in portfolio securities, the securities comprising the Fund's portfolio, changes in interest rates including changes in the relationship between short-term rates and long-term rates, the amount and timing of the use of borrowings and other leverage by the Fund, the effects of leverage on the common shares discussed above under "Leverage," the timing of the investment of leverage proceeds in portfolio securities, the Fund's net assets and its operating expenses. Consequently, the Fund cannot guarantee any particular yield on its shares and the yield for any given period is not an indication or representation of future yields on the Fund's shares.

AUTOMATIC DIVIDEND REINVESTMENT PLAN

Pursuant to the Fund's Automatic Dividend Reinvestment Plan ("Plan"), unless a shareholder is ineligible or elects otherwise, all dividend and capital gains distributions are automatically reinvested by The Bank of New York, as agent for shareholders in administering the Plan ("Plan Agent"), in additional common shares of the Fund. Shareholders may elect to receive distributions in cash. Shareholders who elect to receive cash will be paid by check mailed directly to the shareholder of record (or, if the shares are held in street or other nominee name, then to such nominee) by The Bank of New York, as dividend paying agent at the address set forth below. Participation in the Plan is completely voluntary and may be terminated or resumed at any time without penalty by giving notice in writing to the Plan Agent; such termination will be effective with respect to a particular dividend or distribution if notice is received prior to the record date for the applicable distribution.

Whenever the Fund declares a dividend or distribution payable either in shares or in cash, participants in the Plan will receive the equivalent in shares of common shares. The shares are acquired by the Plan Agent for the participant's account, depending upon the circumstances described below, either
(i) through receipt of additional common shares from the Fund ("newly issued shares") or (ii) by purchase of outstanding common shares on the open market ("open-market purchases") on the New York Stock Exchange or elsewhere. If, on the payment date, the net asset value per share of the common shares is equal to or less than the market price per common share plus estimated brokerage commissions (such condition being referred to herein as "market premium"), the Plan Agent will receive newly issued shares from the Fund for each participant's account. The number of newly issued common shares to be credited to the participant's account will be determined by dividing the dollar amount of the dividend or distribution by the greater of (i) the net asset value per common share on the payment date, or (ii) 95% of the market price per common share on the payment date.

If, on the payment date, the net asset value per common share exceeds the market price plus estimated brokerage commissions (such condition being referred to herein as "market discount"), the Plan Agent has until the last business day before the next date on which the shares trade on an "ex-dividend" basis or in no event more than 30 days after the payment date ("last purchase date") to invest the dividend or distribution amount in shares acquired in open-market purchases. It is contemplated that the Fund will pay monthly income dividends. Therefore, the period during which open-market purchases can be made will exist only from the payment date on the dividend through the date before the next ex- dividend date, which typically will be approximately ten days. The weighted average price (including brokerage commissions) of all common shares purchased by the Plan Agent as Plan Agent will be the price per common share allocable to each participant. If, before the Plan Agent has completed its open-market purchases, the market price of a common share exceeds the net asset value per share, the average per share purchase price paid by the Plan Agent may exceed the net asset value of the Fund's shares, resulting in the acquisition of fewer shares than if the dividend had been paid in newly issued shares on the payment date. Because of the foregoing difficulty with respect to open-market purchases, the Plan provides that if the Plan Agent is unable to invest the full dividend amount in open-market purchases during the purchase period or if the market discount shifts to a market premium during the purchase period, the Plan Agent will cease making open-market purchases and will invest the uninvested portion of the dividend or distribution amount in newly issued shares at the close of business on the last purchase date.

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The Plan Agent maintains all shareholders' accounts in the Plan and furnishes written confirmation of each acquisition made for the participant's account as soon as practicable, but in no event later than 60 days after the date thereof. Shares in the account of each Plan participant will be held by the Plan Agent in non-certificated form in the Plan Agent's name or that of its nominee, and each shareholder's proxy will include those shares purchased or received pursuant to the Plan. The Plan Agent will forward all proxy solicitation materials to participants and vote proxies for shares held pursuant to the Plan first in accordance with the instructions of the participants then with respect to any proxies not returned by such participant, in the same proportion as the Plan Agent votes the proxies returned by the participants.

There will be no brokerage charges with respect to shares issued directly by the Fund as a result of dividends or distributions payable either in shares or in cash. However, each participant will pay a pro rata share of brokerage commissions incurred with respect to the Plan Agent's open-market purchases in connection with the reinvestment of dividends or distributions. If a participant elects to have the Plan Agent sell part or all of his or her common shares and remit the proceeds, such participant will be charged his or her pro rata share of brokerage commissions on the shares sold, plus a $15 transaction fee.

The automatic reinvestment of dividends and distributions will not relieve participants of any federal, state or local income tax that may be payable (or required to be withheld) on such dividends. See "U.S. Federal Income Tax Matters."

Shareholders participating in the Plan may receive benefits not available to shareholders not participating in the Plan. If the market price plus commissions of the Fund's shares is higher than the net asset value, participants in the Plan will receive shares of the Fund at less than they could otherwise purchase them and will have shares with a cash value greater than the value of any cash distribution they would have received on their shares. If the market price plus commissions is below the net asset value, participants receive distributions of shares with a net asset value greater than the value of any cash distribution they would have received on their shares. However, there may be insufficient shares available in the market to make distributions in shares at prices below the net asset value. Also, since the Fund does not redeem its shares, the price on resale may be more or less than the net asset value. See "U.S. Federal Income Tax Matters" for a discussion of tax consequences of the Plan.

Experience under the Plan may indicate that changes are desirable. Accordingly, the Fund reserves the right to amend or terminate the Plan if in the judgment of the Board of Trustees such a change is warranted. The Plan may be terminated by the Plan Agent or the Fund upon notice in writing mailed to each participant at least 60 days prior to the effective date of the termination. Upon any termination, the Plan Agent will cause a certificate or certificates to be issued for the full shares held by each participant under the Plan and cash adjustment for any fraction of a common share at the then current market value of the common shares to be delivered to him or her. If preferred, a participant may request the sale of all of the common shares held by the Plan Agent in his or her Plan account in order to terminate participation in the Plan. If such participant elects in advance of such termination to have the Plan Agent sell part or all of his shares, the Plan Agent is authorized to deduct from the proceeds a $15.00 fee plus the brokerage commissions incurred for the transaction. If a participant has terminated his or her participation in the Plan but continues to have common shares registered in his or her name, he or she may re-enroll in the Plan at any time by notifying the Plan Agent in writing at the address below. The terms and conditions of the Plan may be amended by the Plan Agent or the Fund at any time but, except when necessary or appropriate to comply with applicable law or the rules or policies of the Commission or any other regulatory authority, only by mailing to each participant appropriate written notice at least 30 days prior to the effective date thereof. The amendment shall be deemed to be accepted by each participant unless, prior to the effective date thereof, the Plan Agent receives notice of the termination of the participant's account under the Plan. Any such amendment may include an appointment by the Plan Agent of a successor Plan Agent, subject to the prior written approval of the successor Plan Agent by the Fund. There is no direct service charge to participants in the Plan; however, the Fund reserves the right to amend the Plan to include a service charge payable by the participants.

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All correspondence concerning the Plan as well as requests for additional information should be directed to the Plan Agent at Dividend Reinvestment Department, P.O. Box 1958, Newark, NJ 07101-9774.

CLOSED-END FUND STRUCTURE

The Fund is a newly organized, diversified, closed-end management investment company (commonly referred to as a closed-end fund). Closed-end funds differ from open-end management investment companies (which are generally referred to as mutual funds) in that closed-end funds generally list their shares for trading on a stock exchange and do not redeem their shares at the request of the shareholder. This means that if you wish to sell your shares of a closed-end fund you must trade them on the market like any other stock at the prevailing market price at that time. In a mutual fund, if the shareholder wishes to sell shares of the fund, the mutual fund will redeem or buy back the shares at "net asset value." Also, mutual funds generally offer new shares on a continuous basis to new investors, and closed-end funds generally do not. The continuous inflows and outflows of assets in a mutual fund can make it difficult to manage the fund's investments. By comparison, closed-end funds are generally able to stay more fully invested in securities that are consistent with their investment objectives and also have greater flexibility to make certain types of investments and to use certain investment strategies, such as financial leverage and investments in illiquid securities.

Shares of closed-end funds frequently trade at a discount to their net asset value. To the extent the common shares do trade at a discount, the Fund's Board of Trustees may from time to time engage in open-market repurchases or tender offers for shares after balancing the benefit to shareholders of the increase in the net asset value per share resulting from such purchases against the decrease in the assets of the Fund and potential increase in the expense ratio of the Fund. The Board of Trustees believes that in addition to the beneficial effects described above, any such purchases or tender offers may result in the temporary narrowing of any discount but will not have any long-term effect on the level of any discount. We cannot guarantee or assure, however, that the Fund's Board of Trustees will decide to engage in any of these actions. Nor is there any guarantee or assurance that such actions, if undertaken, would result in the shares trading at a price equal or close to net asset value per share. The Board of Trustees might also consider converting the Fund to an open-end mutual fund, which would also require a vote of the shareholders of the Fund. Conversion of the Fund to an open-end mutual fund would require an amendment to the Fund's Declaration of Trust. Such an amendment would require the favorable vote of the holders of at least 75% of the Fund's outstanding shares (including any preferred shares) entitled to be voted on the matter, voting as a single class (or a majority of such shares if the amendment were previously approved, adopted or authorized by 75% of the total number of Trustees fixed in accordance with the By-Laws), and, assuming preferred shares are issued, the affirmative vote of a majority of outstanding preferred shares, voting as a separate class.

U.S. FEDERAL INCOME TAX MATTERS

The following is a description of certain U.S. federal income tax consequences to a shareholder that acquires, holds and/or disposes of common shares of the Fund. This discussion reflects applicable tax laws of the United States as of the date of this prospectus, which tax laws may be changed or subject to new interpretations by the courts or the IRS, possibly with retroactive effect. No attempt is made to present a detailed explanation of U.S. federal income tax concerns affecting the Fund and its shareholders, and the discussion set forth herein does not constitute tax advice. In addition, no attempt is made to present state, local or foreign tax concerns or tax concerns applicable to an investor with a special tax status such as a financial institution, tax-exempt entity, dealer in securities or non-U.S. investors. Furthermore, this discussion does not reflect possible application of the alternative minimum tax. INVESTORS ARE URGED TO CONSULT THEIR OWN TAX ADVISORS TO DETERMINE THE TAX CONSEQUENCES TO THEM BEFORE INVESTING IN THE FUND.

The Fund intends to elect to be treated, and to qualify each year, as a "regulated investment company" under Subchapter M of the Internal Revenue Code of 1986, as amended (the "Code"), so that

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it will not pay U.S. federal income tax on income and capital gains timely distributed to shareholders. If the Fund qualifies as a regulated investment company and distributes to its shareholders at least 90% of the sum of (i) its "investment company taxable income" as that term is defined in the Code (which includes, among other things, dividends, taxable interest, the excess of any net short-term capital gains over net long-term capital losses and certain net foreign exchange gains as reduced by certain deductible expenses) without regard to the deduction for dividends paid and (ii) the excess of its gross tax-exempt interest, if any, over certain disallowed deductions, the Fund will be relieved of U.S. federal income tax on any income of the Fund, including long-term capital gains, distributed to shareholders. However, if the Fund retains any investment company taxable income or "net capital gain" (the excess of net long-term capital gain over net short-term capital loss), it will be subject to U.S. federal income tax at regular corporate rates (currently at the maximum rate of 35%) on the amount retained. The Fund intends to distribute at least annually all or substantially all of its investment company taxable income, net tax-exempt interest, and net capital gain. Under the Code, the Fund will generally be subject to a nondeductible 4% federal excise tax on the portion of its undistributed ordinary income and capital gains if it fails to meet certain distribution requirements with respect to each calendar year. The Fund intends to make distributions in a timely manner and accordingly does not expect to be subject to this excise tax.

If for any taxable year the Fund did not qualify as a regulated investment company for U.S. federal income tax purposes, it would be treated as a U.S. corporation subject to U.S. federal income tax and distributions to its shareholders would not be deducted by the Fund in computing its taxable income. In such event, the Fund's distributions, to the extent derived from the Fund's current or accumulated earnings and profits, would generally constitute ordinary dividends, which would generally be eligible for the dividends received deduction available to corporate shareholders, and non-corporate shareholders would generally be able to treat such distributions as "qualified dividend income" eligible for reduced rates of U.S. federal income taxation in taxable years beginning on or before December 31, 2008.

Unless a shareholder is ineligible to participate or elects otherwise, all distributions will be automatically reinvested in additional shares of common stock of the Fund pursuant to the Plan. For taxpayers subject to U.S. federal income tax, all dividends will generally be taxable regardless of whether a shareholder takes them in cash or they are reinvested pursuant to the Plan in additional shares of the Fund. Distributions of investment company taxable income are generally taxable as ordinary income to the extent of the Fund's current and accumulated earnings and profits. However, a portion of such distributions derived from certain corporate dividends may qualify for either the dividends received deduction available to corporate shareholders under
Section 243 of the Code or the reduced rates of U.S. federal income taxation for "qualified dividend income" currently available to noncorporate shareholders under Section 1(h)(11) of the Code, provided certain holding period and other requirements are met. Distributions of net capital gain, if any, are generally taxable as long-term capital gains for U.S. federal income tax purposes without regard to the length of time the shareholder has held shares of the Fund. A distribution of an amount in excess of the Fund's current and accumulated earnings and profits, if any, will be treated by a shareholder as a tax-free return of capital, which is applied against and reduces the shareholder's basis in his, her or its shares. To the extent that the amount of any such distribution exceeds the shareholder's basis in his or her shares, the excess will be treated by the shareholder as gain from the sale or exchange of shares. The U.S. federal income tax status of all distributions will be designated by the Fund and reported to the shareholders annually.

If the Fund retains any net capital gain, the Fund may designate the retained amount as undistributed capital gains in a notice to shareholders who, if subject to U.S. federal income tax on long-term capital gains, (i) will be required to include in income as long-term capital gain, their proportionate share of such undistributed amount, and (ii) will be entitled to credit their proportionate share of the tax paid by the Fund on the undistributed amount against their U.S. federal income tax liabilities, if any, and to claim refunds to the extent the credit exceeds such liabilities. If such an event occurs, the tax basis of shares owned by a shareholder of the Fund will, for U.S. federal income tax purposes, generally be increased by the difference between the amount of undistributed net capital gain included in the shareholder's gross income and the tax deemed paid by the shareholders.

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If a shareholder's distributions are automatically reinvested pursuant to the Plan and the Plan Agent invests the distribution in shares acquired on behalf of the shareholder in open-market purchases, for U.S. federal income tax purposes, the shareholder will be treated as having received a taxable distribution in the amount of the cash dividend that the shareholder would have received if the shareholder had elected to receive cash. If a shareholder's distributions are automatically reinvested pursuant to the Plan and the Plan Agent invests the distribution in newly issued shares of the Fund, the shareholder will be treated as receiving a taxable distribution equal to the fair market value of the stock the shareholder receives.

Certain of the Fund's investment practices are subject to special and complex federal income tax provisions that may, among other things, (i) disallow, suspend or otherwise limit the allowance of certain losses or deductions, (ii) convert tax-advantaged, long-term capital gains and qualified dividend income into higher taxed short-term capital gain or ordinary income,
(iii) convert an ordinary loss or a deduction into a capital loss (the deductibility of which is more limited), (iv) cause the Fund to recognize income or gain without a corresponding receipt of cash, (v) adversely affect the timing as to when a purchase or sale of stock or securities is deemed to occur, and
(vi) adversely alter the characterization of certain complex financial transactions. The Fund will monitor its transactions and may make certain tax elections where applicable in order to mitigate the effect of these provisions, if possible.

Dividends, interest and some capital gains received by the Fund on foreign securities may be subject to foreign tax withholdings or other foreign taxes. If applicable, the Fund may make an election under the Code to pass through such taxes to shareholders of the Fund. If such an election is not made, any foreign taxes paid or accrued by the Fund will represent an expense of the Fund. If an election is made, shareholders will generally be able to claim a credit or deduction on their federal income tax return for, and will be required to treat as part of the amounts distributed to them, their pro rata portion of the taxes paid by the Fund to foreign countries with respect to such income.

Sales and other dispositions of the Fund's shares generally are taxable events for shareholders that are subject to U.S. federal income tax. Shareholders should consult their own tax advisors with reference to their individual circumstances to determine whether any particular transaction in the Fund's shares is properly treated as a sale or exchange for tax purposes, as the following discussion assumes, and the tax treatment of any gains or losses recognized in such transactions. Gain or loss will generally be equal to the difference between the amount of cash and the fair market value of other properly realized and the shareholder's adjusted tax basis in the shares sold or exchanged. Such gain or loss will generally be characterized as capital gain or loss and will be long-term or short-term depending on the shareholder's holding period in the shares disposed. However, any loss realized by a shareholder upon the sale or other disposition of shares with a tax holding period of six months or less will be treated as a long-term capital loss to the extent of any amounts treated as distributions of long-term capital gain with respect to such shares. The availability to deduct capital losses may be limited. In addition, losses on sales or other dispositions of shares may be disallowed under the "wash sale" rules in the event that substantially identical shares are acquired (including those made pursuant to reinvestment of dividends) within a period of 61 days beginning 30 days before and ending 30 days after a sale or other disposition of shares. In such a case, the disallowed portion of any loss generally would be included in the U.S. federal tax basis of the shares acquired in the other investments.

The Fund is required in certain circumstances to backup withhold at a current rate of 28% on reportable payments including dividends, capital gain distributions, and proceeds of sales or other dispositions of the Fund's shares paid to certain holders of the Fund's shares who do not furnish the Fund with their correct social security number or other taxpayer identification number and certain other certifications, or who are otherwise subject to backup withholding. Backup withholding is not an additional tax. Any amounts withheld from payments made to a shareholder may be refunded or credited against such shareholder's U.S. federal income tax liability, if any, provided that the required information is furnished to the IRS.

THE FOREGOING IS A GENERAL AND ABBREVIATED SUMMARY OF THE PROVISIONS OF THE CODE AND THE TREASURY REGULATIONS THEREUNDER IN EFFECT AS THEY DIRECTLY GOVERN THE TAXATION OF THE FUND AND ITS SHAREHOLDERS.

43

THESE PROVISIONS ARE SUBJECT TO CHANGE BY LEGISLATIVE OR ADMINISTRATIVE ACTION, AND ANY SUCH CHANGE MAY BE RETROACTIVE. A MORE COMPLETE DISCUSSION OF THE TAX RULES APPLICABLE TO THE FUND CAN BE FOUND IN THE STATEMENT OF ADDITIONAL INFORMATION, WHICH IS INCORPORATED BY REFERENCE INTO THIS PROSPECTUS. SHAREHOLDERS ARE URGED TO CONSULT THEIR TAX ADVISORS REGARDING SPECIFIC QUESTIONS AS TO U.S. FEDERAL, FOREIGN, STATE, AND LOCAL INCOME OR OTHER TAXES BEFORE MAKING AN INVESTMENT IN THE FUND.

NET ASSET VALUE

Net asset value per share is determined as of the close of regular session trading on the New York Stock Exchange (usually 4:00 p.m., Eastern time), on the last business day in each week. Net asset value is calculated by dividing the value of all of the securities and other assets of the Fund, less its liabilities (including accrued expenses and indebtedness) and the aggregate liquidation value of any outstanding preferred shares, by the total number of common shares outstanding. Currently, the net asset values of shares of publicly traded closed-end investment companies are published in Barron's, the Monday edition of The Wall Street Journal and the Monday and Saturday editions of The New York Times.

The values of the securities in the Fund are based on market prices from the primary market in which they are traded. As a general rule, equity securities listed on a U.S. securities exchange are valued at the last current reported sale price as of the time of valuation. Securities quoted on the NASDAQ National Market System are valued at the Nasdaq Official Closing Price ("NOCP"), as determined by Nasdaq, or lacking an NOCP, at the last current reported sale price as of the time of valuation. Bonds and other fixed-income securities that are traded over the counter and on an exchange will be valued according to the broadest and most representative market, and it is expected this will ordinarily be the over-the-counter market. The foreign securities held by the Fund are traded on exchanges throughout the world. Trading on these foreign securities exchanges is completed at various times throughout the day and often does not coincide with the close of trading on the New York Stock Exchange. The value of foreign securities is generally determined at the close of trading of the exchange on which the securities are traded or at the close of trading on the New York Stock Exchange, whichever is earlier.

If market prices are not readily available or the Fund's valuation methods do not produce a value reflective of the fair value of the security, securities and other assets are priced at a fair value determined in accordance with procedures adopted by the Board of Trustees, which may include a systematic fair valuation model provided by an independent service provider.

The Fund also may use fair value pricing if the value of a security it holds has been affected by events occurring before the Fund's pricing time, but after the close of the primary markets or exchanges on which the security is traded. When fair value pricing is employed, the prices of portfolio securities used to calculate the Fund's net asset value may differ from market quotations or official closing prices for the same securities. This means that the Fund may value those securities higher or lower than another fund that uses market quotations or official closing prices.

The fair value pricing procedures recognize that volatility in the U.S. markets may cause prices of foreign securities determined at the close of the foreign market or exchange on which the securities are traded to no longer be reliable when the Fund's net asset value is determined. As a result, at least some of the Fund's foreign securities may be valued at their fair value in accordance with the fair value pricing procedures on any day the Fund calculates its net asset value.

Values of foreign securities are translated from local currencies into U.S. dollars using current exchange rates. Trading in securities in foreign markets takes place on some days (including some weekend days and U.S. holidays) when the NYSE is not open, and does not take place on some days when the NYSE is open. So, the value of the Fund's portfolio may be affected on days when the Fund does not calculate its net asset value.

44

DESCRIPTION OF SHARES

The Fund is authorized to issue an unlimited number of common shares, without par value. The Fund is also authorized to issue preferred shares. Upon the completion of this offering, the Fund will only have common shares outstanding. The Fund's Board of Trustees is authorized, however, to classify and reclassify any unissued shares into one or more additional classes or series of shares. Subject to the limitations of Section 18(c) of the 1940 Act, the Board of Trustees may establish such series or class, including preferred shares, from time to time by setting or changing in any one or more respects the designations, preferences, conversion or other rights, voting powers, restrictions, limitations as to dividends, qualifications or terms or conditions of redemption of such shares and pursuant to such classification or reclassification to increase or decrease the number of authorized shares of any existing class or series. The Board of Trustees, without shareholder approval, is authorized to amend the Fund's Agreement and Declaration of Trust and By-Laws to reflect the terms of any such class or series, including any class of preferred shares. The Fund currently anticipates that it will issue preferred shares as soon as practicable after the closing of this offering. See "Leverage." The Fund is also authorized to issue other securities, including debt securities.

COMMON SHARES

Common shares, when issued and outstanding, will be fully paid and non-assessable. Shareholders are entitled to share pro rata in the net assets of the Fund available for distribution to common shareholders upon liquidation of the Fund. Common shareholders are entitled to one vote for each share held.

In the event that the Fund issues preferred shares and so long as any shares of the Fund's preferred shares are outstanding, holders of common shares will not be entitled to receive any net income of or other distributions from the Fund unless all accumulated dividends on preferred shares have been paid, and unless asset coverage (as defined in the 1940 Act) with respect to preferred shares would be at least 200% after giving effect to such distributions. See "Leverage."

The Fund will send unaudited reports at least semiannually and audited annual financial statements to all of its shareholders.

Calamos provided the initial capital for the Fund by purchasing 6,981 common shares of the Fund for $100,000. As of the date of this prospectus, Calamos owned 100% of the outstanding common shares. Calamos may be deemed to control the Fund until such time as it owns less than 25% of the outstanding shares of the Fund.

PREFERRED SHARES

The Fund currently anticipates issuing, as soon as practicable after the closing of this offering, cumulative preferred shares with an aggregate liquidation preference of up to approximately 33% of the Fund's total assets immediately after issuance. As a non-fundamental policy, the Fund may not issue preferred shares (or borrow money and issue debt securities) with an aggregate liquidation preference (or aggregate principal amount) exceeding 38% of the Fund's total assets. However, the Board of Trustees reserves the right to issue preferred shares to the extent permitted by the 1940 Act, which currently limits the aggregate liquidation preference of all outstanding preferred shares to 50% of the value of the Fund's total assets less the Fund's liabilities and indebtedness. Although the terms of any preferred shares, including dividend rate, liquidation preference and redemption provisions, will be determined by the Fund's Board of Trustees, subject to applicable law and the Fund's Agreement and Declaration of Trust, it is likely that the preferred shares will be structured to carry a relatively short-term dividend rate reflecting interest rates on short-term bonds by providing for the periodic redetermination of the dividend rate at relatively short intervals through an auction, remarketing or other procedure. The Fund also believes that it is likely that the liquidation preference, voting rights and redemption provisions of the preferred shares will be similar to those stated below.

45

In the event of any voluntary or involuntary liquidation, dissolution or winding up of the Fund, the holders of preferred shares will be entitled to receive a preferential liquidating distribution, which is expected to equal the original purchase price per preferred share plus accumulated and unpaid dividends, whether or not declared, before any distribution of assets is made to holders of common shares. After payment of the full amount of the liquidating distribution to which they are entitled, the holders of preferred shares will not be entitled to any further participation in any distribution of assets by the Fund.

The 1940 Act requires that the holders of any preferred shares, voting separately as a single class, have the right to elect at least two Trustees at all times. The remaining Trustees will be elected by holders of common shares and preferred shares, voting together as a single class. In addition, subject to the prior rights, if any, of the holders of any other class of senior securities outstanding, the holders of any preferred shares have the right to elect a majority of the Trustees at any time two years' accumulated dividends on any preferred shares are unpaid. The 1940 Act also requires that, in addition to any approval by shareholders that might otherwise be required, the approval of the holders of a majority of any outstanding preferred shares, voting separately as a class, would be required to (1) adopt any plan of reorganization that would adversely affect the preferred shares, and (2) take any action requiring a vote of security holders under Section 13(a) of the 1940 Act, including, among other things, changes in the Fund's subclassification as a closed-end investment company or changes in its fundamental investment restrictions. See "Certain Provisions of the Agreement and Declaration of Trust and By-Laws." As a result of these voting rights, the Fund's ability to take any such actions may be impeded to the extent that there are any preferred shares outstanding. The Fund's Board of Trustees presently intends that, except as otherwise indicated in this prospectus and except as otherwise required by applicable law, holders of preferred shares will have equal voting rights with holders of common shares (one vote per share, unless otherwise required by the 1940 Act) and will vote together with holders of common shares as a single class.

The affirmative vote of the holders of a majority of the outstanding preferred shares, voting as a separate class, will be required to amend, alter or repeal any of the preferences, rights or powers of holders of preferred shares so as to affect materially and adversely such preferences, rights or powers, or to increase or decrease the authorized number of preferred shares. The class vote of holders of preferred shares described above will in each case be in addition to any other vote required to authorize the action in question.

The terms of the preferred shares are expected to provide that (i) they are redeemable by the Fund in whole or in part at the original purchase price per share plus accrued dividends per share, (ii) the Fund may tender for or purchase preferred shares and (iii) the Fund may subsequently resell any shares so tendered for or purchased. Any redemption or purchase of preferred shares by the Fund will reduce the leverage applicable to the common shares, while any resale of shares by the Fund will increase that leverage.

The discussion above describes the possible offering of preferred shares by the Fund. If the Fund's Board of Trustees determines to proceed with such an offering, the terms of the preferred shares may be the same as, or different from, the terms described above, subject to applicable law and the Agreement and Declaration of Trust. The Board of Trustees, without the approval of the holders of common shares, may authorize an offering of preferred shares or may determine not to authorize such an offering, and may fix the terms of the preferred shares to be offered.

CERTAIN PROVISIONS OF THE AGREEMENT AND
DECLARATION OF TRUST AND BY-LAWS

The Fund's Agreement and Declaration of Trust includes provisions that could have the effect of limiting the ability of other entities or persons to acquire control of the Fund or to change the composition of its Board of Trustees and could have the effect of depriving shareholders of an opportunity to sell their shares at a premium over prevailing market prices by discouraging a third party from seeking to obtain control of the Fund. These provisions, however, have the advantage of potentially requiring persons seeking control of the Fund to negotiate with its management regarding the price to be paid and facilitating the

46

continuity of the Fund's investment objective and policies. The Board of Trustees of the Fund has considered these provisions and concluded that they are in the best interests of the Fund.

The Board of Trustees is divided into three classes and the terms of the Trustees of the different classes are staggered. A Trustee may be removed from office with or without cause by a vote of at least a majority of the then Trustees if such removal is approved by the holders of at least 75% of the shares entitled to vote with respect to the election of such Trustee and present in person or by proxy at a meeting of shareholders called for such purpose.

In addition, the Agreement and Declaration of Trust requires the affirmative vote of at least 75% of the outstanding shares entitled to vote on the matter for the Trust to merge or consolidate with any other corporation, association, trust or other organization or to sell, lease or exchange all or substantially all of the Fund's assets; unless such action has been approved by the affirmative vote of at least 75% of the Trustees then in office, in which case, the affirmative vote of a majority of the outstanding shares entitled to vote on the matter is required.

In addition, conversion of the Fund to an open-end investment company would require an amendment to the Fund's Agreement and Declaration of Trust. Such an amendment would require the favorable vote of a majority of the then Trustees followed by a favorable vote of the holders of at least 75% of the shares entitled to vote on the matter, voting as separate classes or series (or a majority of such shares if the amendment was previously approved by 75% of the Trustees). Such a vote also would satisfy a separate requirement in the 1940 Act that the change be approved by the shareholders.

Under the 1940 Act, shareholders of an open-end investment company may require the company to redeem their shares of common stock at any time (except in certain circumstances as authorized by or under the 1940 Act) at their net asset value, less such redemption charge, if any, as might be in effect at the time of a redemption. If the Fund is converted to an open-end investment company, it could be required to liquidate portfolio securities to meet requests for redemption, and the common shares would no longer be listed on the New York Stock Exchange. Conversion to an open-end investment company would also require changes in certain of the Fund's investment policies and restrictions.

In addition, the Agreement and Declaration of Trust requires the affirmative vote or consent of a majority of the then Trustees followed by the affirmative vote or consent of the holders of at least 75% of the shares of each affected class or series of the Fund outstanding, voting separately as a class or series, to approve, adopt or authorize certain transactions with a Principal Shareholder, unless the transaction has been approved by at least 75% of the Trustees, in which case a majority of the outstanding shares entitled to vote shall be required. For purposes of these provisions, a Principal Shareholder refers to any person who, whether directly or indirectly and whether alone or together with its affiliates and associates, beneficially owns 5% or more of the outstanding shares of any class or series of shares of beneficial interest of the Fund. The 5% holder transactions subject to these special approval requirements are:

- the merger or consolidation of the Fund or any subsidiary of the Fund with or into any Principal Shareholder;

- the issuance of any securities of the Fund to any Principal Shareholder for cash (other than pursuant to an automatic dividend reinvestment plan); or

- the sale, lease or exchange to the Fund or any subsidiary of the Fund in exchange for securities of the Fund, of any assets of any Principal Shareholder, except assets having an aggregate fair market value of less than $1,000,000, aggregating for the purpose of such computation all assets sold, leased or exchanged in any series of similar transactions within a 12-month period.

The Fund may be terminated by the affirmative vote of not less than 75% of the Trustees then in office by written notice to the shareholders.

The Agreement and Declaration of Trust and By-Laws provide that the Board of Trustees has the power to make, alter or repeal any of the By-Laws except for any By-Law that requires a vote of the shareholders to be amended, adopted or repealed by the terms of the Declaration of Trust, By-Laws or

47

law. Neither this provision of the Agreement and Declaration of Trust, nor any of the foregoing provisions thereof requiring the affirmative vote of 75% of outstanding shares of the Fund, can be amended or repealed except by the vote of such required number of shares.

With respect to proposals by shareholders submitted outside the process of Rule 14a-8 of the Securities Exchange Act of 1934, the Fund's By-Laws generally require that advance notice be given to the Fund in the event a shareholder desires to nominate a person for election to the Board of Trustees or to transact any other business that is a proper matter for action by shareholders at an annual meeting of shareholders. With respect to an annual meeting following the first annual meeting of shareholders, notice of any such nomination or business must be delivered to the principal executive offices of the Fund not less than 90 calendar days nor more than 120 calendar days prior to the first anniversary of the date of mailing of the notice for the prior year's annual meeting (subject to certain exceptions). Any notice by a shareholder must be accompanied by certain information as provided in the By-Laws.

48

UNDERWRITING

Citigroup Global Markets Inc., UBS Securities LLC, Advest, Inc., Robert W. Baird & Co. Incorporated, H&R Block Financial Advisors, Inc., Ferris, Baker Watts, Incorporated, Janney Montgomery Scott LLC, Legg Mason Wood Walker, Incorporated, RBC Capital Markets Corporation, Stifel, Nicolaus & Company, Incorporated and Wedbush Morgan Securities Inc. are acting as representatives of the underwriters named below. Subject to the terms and conditions stated in the underwriting agreement dated the date of this prospectus, each underwriter named below has agreed to purchase, and the Fund has agreed to sell to that underwriter, the number of common shares set forth opposite the underwriter's name.

                                                                NUMBER OF
UNDERWRITERS                                                  COMMON SHARES
------------                                                  -------------
Citigroup Global Markets Inc................................
UBS Securities LLC..........................................
Advest, Inc.................................................
Robert W. Baird & Co. Incorporated..........................
H&R Block Financial Advisors, Inc...........................
Ferris, Baker Watts, Incorporated...........................
Janney Montgomery Scott LLC.................................
Legg Mason Wood Walker, Incorporated........................
RBC Capital Markets Corporation.............................
Stifel, Nicolaus & Company, Incorporated....................
Wedbush Morgan Securities Inc...............................
                                                                ---------
     Total..................................................
                                                                =========

The underwriting agreement provides that the obligations of the underwriters to purchase the common shares included in this offering are subject to approval of legal matters by counsel and to other conditions. The underwriters are obligated to purchase all the common shares (other than those covered by the over-allotment option described below) if they purchase any of the common shares.

The underwriters propose to offer some of the common shares directly to the public at the public offering price set forth on the cover page of this prospectus and some of the common shares to dealers at the public offering price less a concession not to exceed $ per common share. The sales load the Fund will pay of $0.675 per common share is equal to 4.50% of the initial offering price. The underwriters may allow, and dealers may reallow, a concession not to exceed $ per common share on sales to other dealers. If all of the common shares are not sold at the initial offering price, the representatives may change the public offering price and the other selling terms. Investors must pay for any common shares purchased on or before , 2005. The representatives have advised the Fund that the underwriters do not intend to confirm any sales to any accounts over which they exercise discretionary authority.

The Fund has granted to the underwriters an option, exercisable for 45 days from the date of this prospectus, to purchase up to additional common shares at the public offering price less the sales load. The underwriters may exercise the option solely for the purpose of covering over-allotments, if any, in connection with this offering. To the extent the option is exercised, each underwriter must purchase a number of additional common shares approximately proportionate to that underwriter's initial purchase commitment.

The Fund and Calamos have agreed that, for a period of 180 days from the date of this prospectus, they will not, without the prior written consent of Citigroup Global Markets Inc., dispose of or hedge any common shares or any securities convertible into or exchangeable for common shares. Citigroup Global Markets Inc., in its sole discretion, may release any of the securities subject to these lock-up agreements at any time without notice.

49

Prior to this offering, there has been no public market for the common shares. Consequently, the initial public offering price for the common shares was determined by negotiations among the Fund, Calamos and the representatives. There can be no assurance, however, that the price at which the common shares will sell in the public market after this offering will not be lower than the initial public offering price or that an active trading market in the common shares will develop and continue after this offering.

The common shares have been approved for listing on the New York Stock Exchange under the symbol "CGO". The underwriters have undertaken to sell common shares to a minimum of 2,000 beneficial owners in lots of 100 or more shares to meet the New York Stock Exchange distribution requirements for trading.

The following table shows the sales load that the Fund will pay to the underwriters in connection with this offering. These amounts are shown assuming both no exercise and full exercise of the underwriters' option to purchase additional common shares.

                                                                     PAID BY FUND
                                                              ---------------------------
                                                              NO EXERCISE   FULL EXERCISE
                                                              -----------   -------------
Per share...................................................    $              $
Total.......................................................    $              $

The Fund and Calamos have each agreed to indemnify the several underwriters against certain liabilities, including liabilities under the Securities Act of 1933, as amended, or to contribute to payments the underwriters may be required to make because of any of these liabilities.

The Fund has agreed to pay the underwriters $0.005 per common share as a partial reimbursement of expenses incurred in connection with the offering, as well as to reimburse the underwriters for certain legal expenses. Calamos has agreed to pay the amount by which the Fund's organizational expenses and offering costs (other than the sales load but inclusive of the reimbursement of underwriter expenses) exceed $0.03 per share.

Additional Compensation to Underwriters. Calamos (and not the Fund) will pay to Citigroup Global Markets Inc. and UBS Securities LLC from its own assets structuring fees for advice relating to the structure and design of the Fund and the organization of the Fund as well as services related to the sale and distribution of the common shares in amounts equal to $ and $ , respectively, which are % and % of the total initial price to the public of the common shares offered hereby. In accordance with the rules of the National Association of Securities Dealers, Inc., the sum of the noted fees to be paid to Citigroup Global Markets Inc. and UBS Securities LLC, the amounts paid by the Fund to reimburse certain underwriter expenses discussed above and the sales load to be paid by the Fund will not exceed 9.00% of the total initial price to the public of the common shares offered hereby.

Certain underwriters may make a market in the common shares after trading in the common shares has commenced on the New York Stock Exchange. No underwriter is, however, obligated to conduct market-making activities and any such activities may be discontinued at any time without notice, at the sole discretion of the underwriter. No assurance can be given as to the liquidity of, or the trading market for, the common shares as a result of any market-making activities undertaken by any underwriter. This prospectus is to be used by any underwriter in connection with the offering and, during the period in which a prospectus must be delivered, with offers and sales of the common shares in market-making transactions in the over-the-counter market at negotiated prices related to prevailing market prices at the time of the sale.

In connection with the offering, Citigroup Global Markets Inc., on behalf of the underwriters, may purchase and sell common shares in the open market. These transactions may include short sales, syndicate covering transactions and stabilizing transactions. Short sales involve syndicate sales of common shares in excess of the number of common shares to be purchased by the underwriters in the offering, which creates a syndicate short position. "Covered" short sales are sales of common shares made in an amount up to the number of common shares represented by the underwriters' over-allotment option. In determining the source of common shares to close out the covered syndicate short position, the

50

underwriters will consider, among other things, the price of common shares available for purchase in the open market as compared to the price at which they may purchase common shares through the over-allotment option. Transactions to close out the covered syndicate short involve either purchases of common shares in the open market after the distribution has been completed or the exercise of the over-allotment option. The underwriters may also make "naked" short sales of common shares in excess of the over-allotment option. The underwriters must close out any naked short position by purchasing common shares in the open market. A naked short position is more likely to be created if the underwriters are concerned that there may be downward pressure on the price of common shares in the open market after pricing that could adversely affect investors who purchase in the offering. Stabilizing transactions consist of bids for or purchases of common shares in the open market while the offering is in progress.

The underwriters also may impose a penalty bid. Penalty bids permit the underwriters to reclaim a selling concession from a syndicate member when Citigroup Global Markets Inc. repurchases common shares originally sold by that syndicate member in order to cover syndicate short positions or make stabilizing purchases.

Any of these activities may have the effect of preventing or retarding a decline in the market price of common shares. They may also cause the price of common shares to be higher than the price that would otherwise exist in the open market in the absence of these transactions. The underwriters may conduct these transactions on the New York Stock Exchange or in the over-the-counter market, or otherwise. If the underwriters commence any of these transactions, they may discontinue them at any time.

A prospectus in electronic format may be made available on the websites maintained by one or more of the underwriters. The representatives may agree to allocate a number of common shares to underwriters for sale to their online brokerage account holders. The representatives will allocate common shares to underwriters that may make Internet distributions on the same basis as other allocations. In addition, common shares may be sold by the underwriters to securities dealers who resell common shares to online brokerage account holders.

The Fund anticipates that, from time to time, certain underwriters may act as brokers or dealers in connection with the execution of the Fund's portfolio transactions after they have ceased to be underwriters and, subject to certain restrictions, may act as brokers while they are underwriters.

Certain underwriters have performed investment banking and advisory services for Calamos and its affiliates from time to time, for which they have received customary fees and expenses. Certain underwriters may, from time to time, engage in transactions with or perform services for Calamos and its affiliates in the ordinary course of business.

Prior to the initial public offering of common shares, Calamos purchased common shares from the Fund in an amount satisfying the net worth requirements of Section 14(a) of the 1940 Act.

The principal business address of Citigroup Global Markets Inc. is 388 Greenwich Street, New York, NY 10013.

CUSTODIAN, TRANSFER AGENT AND DIVIDEND DISBURSING AGENT

The Fund's securities and cash are held under a custodian agreement with The Bank of New York, One Wall Street, New York, New York 10286. The transfer agent and dividend disbursing agent for the Fund's shares is also The Bank of New York.

LEGAL OPINIONS

Bell, Boyd & Lloyd LLC, Chicago, Illinois, serves as counsel to the Fund and to the non-interested Trustees. Vedder, Price, Kaufman & Kammholz, P.C. ("Vedder Price"), Chicago, Illinois, which is serving as special counsel to the Fund in connection with the offering, will pass on the legality of the shares offered hereby. Vedder Price is also counsel to Calamos. Certain matters will be passed upon for the underwriters by Simpson Thacher & Bartlett LLP, New York, New York. Vedder Price and Simpson Thacher & Bartlett LLP may rely on matters of Delaware law on the opinion of Morris, Nichols, Arsht & Tunnell, Wilmington, Delaware.

51

TABLE OF CONTENTS OF

THE STATEMENT OF ADDITIONAL INFORMATION

Use of Proceeds.............................................   S-1
Investment Restrictions.....................................  S-21
Management of the Fund......................................  S-23
Portfolio Managers..........................................  S-31
Portfolio Transactions......................................  S-31
Repurchase of Common Shares.................................  S-32
U.S. Federal Income Tax Matters.............................  S-34
Experts.....................................................  S-40
Additional Information......................................  S-40
Financial Statements........................................   F-1
Appendix A -- Description of Ratings........................   A-1

52

Until , 2005 (25 days after the date of this prospectus), all dealers that buy, sell or trade the common shares, whether or not participating in this offering, may be required to deliver a prospectus. This is in addition to the dealers' obligation to deliver a prospectus when acting as underwriters and with respect to their unsold allotments or subscriptions.
4,000,000 SHARES

CALAMOS GLOBAL TOTAL RETURN FUND

COMMON SHARES OF BENEFICIAL INTEREST PROSPECTUS
, 2005
CITIGROUP
UBS INVESTMENT BANK
ADVEST, INC.
ROBERT W. BAIRD & CO.
H&R BLOCK FINANCIAL ADVISORS, INC.
FERRIS, BAKER WATTS
INCORPORATED

JANNEY MONTGOMERY SCOTT LLC
LEGG MASON WOOD WALKER
INCORPORATED

RBC CAPITAL MARKETS
STIFEL, NICOLAUS & COMPANY
INCORPORATED

WEDBUSH MORGAN SECURITIES INC.

SEC FILE NUMBER: 811-21547
333-114111
CGOIPOPRO 10/05 3051


The information in this Statement of Additional Information is not complete and may be changed. We may not sell these securities until the Registration Statement filed with the Securities and Exchange Commission is effective. This Statement of Additional Information is not an offer to sell these securities and is not soliciting an offer to buy these securities in any state where the offer or sale is not permitted.

SUBJECT TO COMPLETION, DATED OCTOBER 25, 2005

CALAMOS GLOBAL TOTAL RETURN FUND

STATEMENT OF ADDITIONAL INFORMATION

Calamos Global Total Return Fund (the "Fund") is a newly organized, diversified, closed-end management investment company. This Statement of Additional Information relating to common shares does not constitute a prospectus, but should be read in conjunction with the Prospectus relating thereto dated ________ __, 2005. This Statement of Additional Information does not include all information that a prospective investor should consider before purchasing common shares, and investors should obtain and read the Prospectus prior to purchasing such shares. A copy of the Prospectus may be obtained without charge by calling 1-800-582-6959. You may also obtain a copy of the Prospectus on the Securities and Exchange Commission's web site (http://www.sec.gov).

Use of Proceeds................................................................................................S-1
Investment Restrictions.......................................................................................S-21
Management of the Fund........................................................................................S-23
Portfolio Managers............................................................................................S-31
Portfolio Transactions........................................................................................S-31
Repurchase of Common Shares...................................................................................S-32
U.S. Federal Income Tax Matters...............................................................................S-34
Experts.......................................................................................................S-40
Additional Information........................................................................................S-40
Financial Statements...........................................................................................F-1
Appendix A--Description of Ratings.............................................................................A-1

This Statement of Additional Information is dated _______ __, 2005.


USE OF PROCEEDS

The Fund will invest the net proceeds of the offering in accordance with the Fund's investment objective and policies as stated below and in the Prospectus. It is presently anticipated that the Fund will invest substantially all of the net proceeds in securities that meet the investment objective and policies within three months after completion of the offering. Pending such investment, the net proceeds may be invested in U.S. government securities and high grade, short-term money market instruments. If necessary, the Fund may also purchase, as temporary investments, securities of other open- or closed-end investment companies that invest primarily in the types of securities in which the Fund may invest directly.

INVESTMENT OBJECTIVE AND POLICIES

The prospectus presents the investment objective and the principal investment strategies and risks of the Fund. This section supplements the disclosure in the Fund's prospectus and provides additional information on the Fund's investment policies or restrictions. Restrictions or policies stated as a maximum percentage of the Fund's assets are only applied immediately after a portfolio investment to which the policy or restriction is applicable (other than the limitations on borrowing). Accordingly, any later increase or decrease resulting from a change in values, net assets or other circumstances will not be considered in determining whether the investment complies with the Fund's restrictions and policies.

PRIMARY INVESTMENTS. Under normal circumstances, the Fund will invest primarily in a portfolio of equity securities, convertible securities and other income producing securities such as investment grade and below investment grade (high yield/high risk) debt securities. The Fund, under normal circumstances, will invest at least 50% of its managed assets in equity securities (including securities that are convertible into equity securities). The Fund may invest up to 100% of its managed assets in securities of foreign issuers, including debt and equity securities of corporate issuers and debt securities of government issuers, in developed and emerging markets. Under normal circumstances, the Fund will invest at least 30% of its managed assets in securities of foreign issuers. The Fund will invest in the securities of issuers of several different countries throughout the world, in addition to the United States. "Managed Assets" means the total assets of the Fund (including any assets attributable to any leverage that may be outstanding) minus the sum of accrued liabilities (other than debt representing financial leverage). For this purpose the liquidation preference on any preferred shares will not constitute a liability.

The Fund will attempt to keep a consistent balance between risk and reward over the course of different market cycles, through various combinations of stocks, bonds, and/or convertible securities, to achieve what the investment adviser, Calamos Advisors, LLC ("Calamos"), believes to be an appropriate blend for the then current market. As the market environment changes, portfolio securities may change in an attempt to achieve a relatively consistent risk level over time. At some points in a market cycle, one type of security may make up a substantial portion of the portion of the portfolio, while at other times certain securities may have minimal or no representation, depending on market conditions.

FOREIGN SECURITIES. The Fund may invest up to 100% of its managed assets in securities of foreign issuers, including debt and equity securities of corporate issuers and debt securities of government issuers, in developed and emerging markets. The Fund expects that it initially will invest more than 50% of its managed assets in securities of foreign issuers, which percentage may change over time, depending on Calamos' ongoing assessment of market opportunities for the Fund. Under normal circumstances, the Fund will invest at least 30% of its managed assets in securities of foreign issuers. The Fund will invest in the securities of issuers of several different countries throughout the world, in addition to the United States. A foreign issuer is a company organized under the laws of a foreign country. For these purposes, foreign securities includes American Depositary Receipts ("ADRs") or securities guaranteed by a United States person and foreign securities in the form of European Depositary Receipts ("EDRs"), Global Depositary Receipts ("GDRs") or other securities representing underlying shares of foreign issuers. Positions in those securities are not necessarily denominated in the same currency as the common stocks into which they may be converted. ADRs are receipts typically issued by an American bank or trust company evidencing ownership of the underlying securities. EDRs

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are European receipts listed on the Luxembourg Stock Exchange evidencing a similar arrangement. GDRs are U.S. dollar-denominated receipts evidencing ownership of foreign securities. Generally, ADRs, in registered form, are designed for the U.S. securities markets and EDRs and GDRs, in bearer form, are designed for use in foreign securities markets. The Fund may invest in sponsored or unsponsored ADRs. In the case of an unsponsored ADR, the Fund is likely to bear its proportionate share of the expenses of the depository and it may have greater difficulty in receiving shareholder communications than it would have with a sponsored ADR. To the extent positions in portfolio securities are denominated in foreign currencies, the Fund's investment performance is affected by the strength or weakness of the U.S. dollar against those currencies. For example, if the dollar falls in value relative to the Japanese yen, the dollar value of a Japanese stock held in the portfolio will rise even though the price of the stock remains unchanged. Conversely, if the dollar rises in value relative to the yen, the dollar value of the Japanese stock will fall. (See discussion of transaction hedging and portfolio hedging below under "Currency Exchange Transactions.")

Investors should understand and consider carefully the risks involved in foreign investing. Investing in foreign securities, which are generally denominated in foreign currencies, and utilization of forward foreign currency exchange contracts involve certain considerations comprising both risks and opportunities not typically associated with investing in U.S. securities. These considerations include: fluctuations in exchange rates of foreign currencies; possible imposition of exchange control regulation or currency restrictions that would prevent cash from being brought back to the United States; less public information with respect to issuers of securities; less governmental supervision of stock exchanges, securities brokers, and issuers of securities; lack of uniform accounting, auditing and financial reporting standards; lack of uniform settlement periods and trading practices; less liquidity and frequently greater price volatility in foreign markets than in the United States; possible imposition of foreign taxes; and sometimes less advantageous legal, operational and financial protections applicable to foreign sub-custodial arrangements.

Although the Fund intends to invest in companies and government securities of countries having stable political environments, there is the possibility of expropriation or confiscatory taxation, seizure or nationalization of foreign bank deposits or other assets, establishment of exchange controls, the adoption of foreign government restrictions, or other adverse political, social or diplomatic developments that could affect investment in these nations.

The Fund may invest in the securities of emerging countries. The securities markets of emerging countries are substantially smaller, less developed, less liquid and more volatile than the securities markets of the U.S. and other more developed countries. Disclosure and regulatory standards in many respects are less stringent than in the U.S. and other major markets. There also may be a lower level of monitoring and regulation of emerging markets and the activities of investors in such markets, and enforcement of existing regulations has been extremely limited. Economies in individual emerging markets may differ favorably or unfavorably from the U.S. economy in such respects as growth of gross domestic product, rates of inflation, currency depreciation, capital reinvestment, resource self-sufficiency and balance of payments positions. Many emerging market countries have experienced high rates of inflation for many years, which has had and may continue to have very negative effects on the economies and securities markets of those countries.

An investment in debt obligations of non-U.S. governments and their political subdivisions (sovereign debt) involves special risks that are not present in corporate debt obligations. The non-U.S. issuer of the sovereign debt or the non-U.S. governmental authorities that control the repayment of the debt may be unable or unwilling to repay principal or interest when due, and the Fund may have limited recourse in the event of a default. During periods of economic uncertainty, the market prices of sovereign debt may be more volatile than prices of debt obligations of U.S. issuers. In the past, certain non-U.S. countries have encountered difficulties in servicing their debt obligations, withheld payments of principal and interest and declared moratoria on the payment of principal and interest on their sovereign debt.

A sovereign debtor's willingness or ability to repay principal and pay interest in a timely manner may be affected by, among other factors, its cash flow situation, the extent of its foreign currency reserves, the availability of sufficient non-U.S. currency, the relative size of the debt service burden, the sovereign debtor's policy toward its principal international lenders and local political constraints.

Sovereign debtors may also be dependent on expected disbursements from non-U.S. governments, multilateral agencies and other entities to reduce principal and interest arrearages on their debt. The failure of a sovereign debtor to implement economic reforms, achieve specified levels of economic performance or repay principal or interest when due may result in the cancellation of third-party commitments to lend funds to the sovereign debtor, which may further impair such debtor's ability or willingness to service its debts.
CURRENCY EXCHANGE TRANSACTIONS. Currency exchange transactions may be conducted either on a spot (i.e., cash) basis at the spot rate for purchasing or selling currency prevailing in the foreign exchange market or through forward currency exchange contracts ("forward contracts"). Forward contracts are contractual agreements to purchase or sell a specified currency at a specified future date (or within a specified time period) and price set at the time of the contract. Forward contracts are usually

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entered into with banks, foreign exchange dealers and broker-dealers, are not exchange traded, and are usually for less than one year, but may be renewed.

Forward currency exchange transactions may involve currencies of the different countries in which the Fund may invest and serve as hedges against possible variations in the exchange rate between these currencies. Currency exchange transactions are limited to transaction hedging and portfolio hedging involving either specific transactions or portfolio positions, except to the extent described below under "Synthetic Foreign Money Market Positions." Transaction hedging is the purchase or sale of forward contracts with respect to specific receivables or payables of the Fund accruing in connection with the purchase and sale of its portfolio securities or the receipt of dividends or interest thereon. Portfolio hedging is the use of forward contracts with respect to portfolio security positions denominated or quoted in a particular foreign currency. Portfolio hedging allows the Fund to limit or reduce its exposure in a foreign currency by entering into a forward contract to sell such foreign currency (or another foreign currency that acts as a proxy for that currency) at a future date for a price payable in U.S. dollars so that the value of the foreign denominated portfolio securities can be approximately matched by a foreign denominated liability. The Fund may not engage in portfolio hedging with respect to the currency of a particular country to an extent greater than the aggregate market value (at the time of making such sale) of the securities held in its portfolio denominated or quoted in that particular currency, except that the Fund may hedge all or part of its foreign currency exposure through the use of a basket of currencies or a proxy currency where such currencies or currency act as an effective proxy for other currencies. In such a case, the Fund may enter into a forward contract where the amount of the foreign currency to be sold exceeds the value of the securities denominated in such currency. The use of this basket hedging technique may be more efficient and economical than entering into separate forward contracts for each currency held in the Fund. The Fund may not engage in "speculative" currency exchange transactions.

If the Fund enters into a forward contract, the Fund's custodian will segregate liquid assets of the Fund having a value equal to the Fund's commitment under such forward contract. At the maturity of the forward contract to deliver a particular currency, the Fund may either sell the portfolio security related to the contract and make delivery of the currency, or it may retain the security and either acquire the currency on the spot market or terminate its contractual obligation to deliver the currency by purchasing an offsetting contract with the same currency trader obligating it to purchase on the same maturity date the same amount of the currency. It is impossible to forecast with absolute precision the market value of portfolio securities at the expiration of a forward contract. Accordingly, it may be necessary for a Fund to purchase additional currency on the spot market (and bear the expense of such purchase) if the market value of the security is less than the amount of currency the Fund is obligated to deliver and if a decision is made to sell the security and make delivery of the currency. Conversely, it may be necessary to sell on the spot market some of the currency received upon the sale of the portfolio security if its market value exceeds the amount of currency the Fund is obligated to deliver.

If the Fund retains the portfolio security and engages in an offsetting transaction, the Fund will incur a gain or a loss to the extent that there has been movement in forward contract prices. If the Fund engages in an offsetting transaction, it may subsequently enter into a new forward contract to sell the currency. Should forward prices decline during the period between the Fund's entering into a forward contract for the sale of a currency and the date it enters into an offsetting contract for the purchase of the currency, the Fund will realize a gain to the extent the price of the currency it has agreed to sell exceeds the price of the currency it has agreed to purchase. Should forward prices increase, the Fund will suffer a loss to the extent the price of the currency it has agreed to purchase exceeds the price of the currency it has agreed to sell. A default on the contract would deprive the Fund of unrealized profits or force the Fund to cover its commitments for purchase or sale of currency, if any, at the current market price.

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Hedging against a decline in the value of a currency does not eliminate fluctuations in the value of a portfolio security traded in that currency or prevent a loss if the value of the security declines. Hedging transactions also preclude the opportunity for gain if the value of the hedged currency should rise. Moreover, it may not be possible for the Fund to hedge against a devaluation that is so generally anticipated that the Fund is not able to contract to sell the currency at a price above the devaluation level it anticipates. The cost to the Fund of engaging in currency exchange transactions varies with such factors as the currency involved, the length of the contract period, and prevailing market conditions. Because currency exchange transactions are usually conducted on a principal basis, no fees or commissions are involved.

EQUITY SECURITIES. Equity securities include common and preferred stocks, warrants, rights, and depository receipts. Under normal circumstances, the Fund will invest at least 50% of its managed assets in equity securities (including securities that are convertible into equity securities). An investment in the equity securities of a company represents a proportionate ownership interest in that company. Therefore, the Fund participates in the financial success or failure of any company in which it has an equity interest. Equity investments are subject to greater fluctuations in market value than other asset classes as a result of such factors as a company's business performance, investor perceptions, stock market trends and general economic conditions. Equity securities are subordinated to bonds and other debt instruments in a company's capital structure in terms of priority to corporate income and liquidation payments.

Preferred stocks involve credit risk, which is the risk that a preferred stock in the Fund's portfolio will decline in price or fail to make dividend payments when due because the issuer of the security experiences a decline in its financial status. In addition to credit risk, investments in preferred stocks involve certain other risks. Certain preferred stocks contain provisions that allow an issuer under certain circumstances to skip distributions (in the case of "non-cumulative" preferred stocks) or defer distributions (in the case of "cumulative" preferred stocks). If the Fund owns a preferred stock that is deferring its distributions, the Fund may be required to report income for tax purposes while it is not receiving income from that stock. In certain varying circumstances, an issuer may redeem its preferred stock prior to a specified date in the event of certain tax or legal changes or at the issuer's call. In the event of a redemption, the Fund may not be able to reinvest the proceeds at comparable rates of return. Preferred stocks typically do not provide any voting rights, except in cases when dividends are in arrears for a specified number of periods.

Equity securities of small and mid cap companies historically have been subject to greater investment risk than those of large companies. The risks generally associated with small and medium-sized companies include more limited product lines, markets and financial resources, lack of management depth or experience, dependency on key personnel and vulnerability to adverse market and economic developments. Accordingly, the prices of small and medium-sized company equity securities tend to be more volatile than prices of large company stocks. Further, the prices of small and medium-sized company equity securities are often adversely affected by limited trading volumes and the lack of publicly available information.

DEBT SECURITIES. In pursuing its investment objective, the Fund may invest in convertible and non-convertible debt securities, including lower-rated securities (i.e., securities rated BB or lower by Standard & Poor's Corporation, a division of The McGraw-Hill Companies ("S&P"), or Ba or lower by Moody's Investor Services, Inc. ("Moody's")) and securities that are not rated but are considered by Calamos to be of similar quality. There are no restrictions as to the ratings of debt securities acquired by the Fund or the portion of the Fund's assets that may be invested in debt securities in a particular ratings category.

Securities rated BBB or Baa are considered to be medium grade and to have speculative characteristics. Lower-rated debt securities are predominantly speculative with respect to the issuer's capacity to pay interest and repay principal. Investment in medium- or lower-quality debt securities involves greater investment risk, including the possibility of issuer default or bankruptcy. An economic downturn could severely disrupt the market for such securities and adversely affect the value of such securities. In addition, lower-quality bonds are less sensitive to interest rate changes than higher-quality instruments and generally are more sensitive to adverse economic changes or individual corporate developments. During a period of adverse economic changes, including a period of rising interest rates, issuers of such bonds may experience difficulty in servicing their principal and interest payment obligations.

Achievement by the Fund of its investment objective will be more dependent on Calamos' credit analysis than would be the case if the Fund were investing in higher-quality debt securities. Because the ratings of rating services (which evaluate the safety of principal and interest payments, not market risks) are used only as preliminary indicators of investment quality, Calamos employs its own credit research and analysis. These analyses may take into consideration such quantitative factors as an issuer's present and potential liquidity, profitability, internal capability to generate funds, debt/equity ratio and debt servicing capabilities, and such qualitative factors as an assessment of management, industry characteristics, accounting methodology, and foreign business exposure.

Medium- and lower-quality debt securities may be less marketable than higher-quality debt securities because the market for them is less broad. The market for unrated debt securities is even narrower. During periods of thin trading in these markets, the spread between bid and asked prices is likely to increase significantly, and the Fund may have greater difficulty selling its portfolio securities. The market value of these securities and their liquidity may be affected by adverse publicity and investor perceptions.

HIGH YIELD SECURITIES. The high yield securities in which the Fund invests are rated below investment grade (i.e. rated Ba or lower by Moody's or BB or lower by Standard & Poor's) or are unrated but determined by Calamos to be of comparable quality.

INVESTMENT IN HIGH YIELD SECURITIES INVOLVES SUBSTANTIAL RISK OF LOSS. Below investment grade non-convertible debt securities or comparable unrated securities are commonly referred to as "junk bonds" and are considered predominantly speculative with respect to the issuer's ability to pay interest

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and principal and are susceptible to default or decline in market value due to adverse economic and business developments. The market values for high yield securities tend to be very volatile, and these securities are less liquid than investment grade debt securities. For these reasons, your investment in the Fund is subject to the following specific risks:

- increased price sensitivity to changing interest rates and to a deteriorating economic environment;

- greater risk of loss due to default or declining credit quality;

- adverse company specific events are more likely to render the issuer unable to make interest and/or principal payments; and

- if a negative perception of the high yield market develops, the price and liquidity of high yield securities may be depressed. This negative perception could last for a significant period of time.

Securities rated below investment grade are speculative with respect to the capacity to pay interest and repay principal in accordance with the terms of such securities. A rating of C from Moody's means that the issue so rated can be regarded as having extremely poor prospects of ever attaining any real investment standing. Standard & Poor's assigns a rating of C to issues that are currently highly vulnerable to nonpayment, and the C rating may be used to cover a situation where a bankruptcy petition has been filed or similar action taken, but payments on the obligation are being continued (a C rating is also assigned to a preferred stock issue in arrears on dividends or sinking fund payments, but that is currently paying). See Appendix A to this statement of additional information for a description of Moody's and Standard & Poor's ratings.

Adverse changes in economic conditions are more likely to lead to a weakened capacity of a high yield issuer to make principal payments and interest payments than an investment grade issuer. The principal amount of high yield securities outstanding has proliferated in the past decade as an increasing number of issuers have used high yield securities for corporate financing. An economic downturn could severely affect the ability of highly leveraged issuers to service their debt obligations or to repay their obligations upon maturity. Similarly, down-turns in profitability in specific industries could adversely affect the ability of high yield issuers in that industry to meet their obligations. The market values of lower quality debt securities tend to reflect individual developments of the issuer to a greater extent than do higher quality securities, which react primarily to fluctuations in the general level of interest rates. Factors having an adverse impact on the market value of lower quality securities may have an adverse effect on the Fund's net asset value and the market value of its common shares. In addition, the Fund may incur additional expenses to the extent it is required to seek recovery upon a default in payment of principal or interest on its portfolio holdings. In certain circumstances, the Fund may be required to foreclose on an issuer's assets and take possession of its property or operations. In such circumstances, the Fund would incur additional costs in disposing of such assets and potential liabilities from operating any business acquired.

The secondary market for high yield securities may not be as liquid as the secondary market for more highly rated securities, a factor that may have an adverse effect on the Fund's ability to dispose of a particular security when necessary to meet its liquidity needs. There are fewer dealers in the market for high yield securities than investment grade obligations. The prices quoted by different dealers may vary significantly and the spread between the bid and asked price is generally much larger than higher quality instruments. Under adverse market or economic conditions, the secondary market for high yield securities could contract further, independent of any specific adverse changes in the condition of a particular issuer, and these instruments may become illiquid. As a result, the Fund could find it more

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difficult to sell these securities or may be able to sell the securities only at prices lower than if such securities were widely traded. Prices realized upon the sale of such lower rated or unrated securities, under these circumstances, may be less than the prices used in calculating the Fund's net asset value.

Since investors generally perceive that there are greater risks associated with lower quality debt securities of the type in which the Fund may invest a portion of its assets, the yields and prices of such securities may tend to fluctuate more than those for higher rated securities. In the lower quality segments of the debt securities market, changes in perceptions of issuers' creditworthiness tend to occur more frequently and in a more pronounced manner than do changes in higher quality segments of the debt securities market, resulting in greater yield and price volatility.

If the Fund invests in high yield securities that are rated C or below, the Fund will incur significant risk in addition to the risks associated with investments in high yield securities and corporate loans. Distressed securities frequently do not produce income while they are outstanding. The Fund may purchase distressed securities that are in default or the issuers of which are in bankruptcy. The Fund may be required to bear certain extraordinary expenses in order to protect and recover its investment.

DISTRESSED SECURITIES. The Fund may, but currently does not intend to, invest up to 5% of its total assets in distressed securities, including corporate loans, which are the subject of bankruptcy proceedings or otherwise in default as to the repayment of principal and/or payment of interest at the time of acquisition by the Fund or are rated in the lower rating categories (Ca or lower by Moody's or CC or lower by Standard & Poor's) or which are unrated investments considered by Calamos to be of comparable quality. Investment in distressed securities is speculative and involves significant risk. Distressed securities frequently do not produce income while they are outstanding and may require the Fund to bear certain extraordinary expenses in order to protect and recover its investment. Therefore, to the extent the Fund seeks capital appreciation through investment in distressed securities, the Fund's ability to achieve current income for its shareholders may be diminished. The Fund also will be subject to significant uncertainty as to when and in what manner and for what value the obligations evidenced by the distressed securities will eventually be satisfied (e.g., through a liquidation of the obligor's assets, an exchange offer or plan of reorganization involving the distressed securities or a payment of some amount in satisfaction of the obligation). In addition, even if an exchange offer is made or a plan of reorganization is adopted with respect to distressed securities held by the Fund, there can be no assurance that the securities or other assets received by the Fund in connection with such exchange offer or plan of reorganization will not have a lower value or income potential than may have been anticipated when the investment was made. Moreover, any securities received by the Fund upon completion of an exchange offer or plan of reorganization may be restricted as to resale. As a result of the Fund's participation in negotiations with respect to any exchange offer or plan of reorganization with respect to an issuer of distressed securities, the Fund may be restricted from disposing of such securities.

LOANS. The Fund may invest up to 5% of its total assets in loan participations and other direct claims against a borrower. The corporate loans in which the Fund invests primarily consist of direct obligations of a borrower and may include debtor in possession financings pursuant to Chapter 11 of the U.S. Bankruptcy Code, obligations of a borrower issued in connection with a restructuring pursuant to Chapter 11 of the U.S. Bankruptcy Code, leveraged buy-out loans, leveraged recapitalization loans, receivables purchase facilities, and privately placed notes. The Fund may invest in a corporate loan at origination as a co-lender or by acquiring in the secondary market participations in, assignments of or novations of a corporate loan. By purchasing a participation, the Fund acquires some or all of the interest of a bank or other lending institution in a loan to a corporate or government borrower. The participations typically will result in the Fund having a contractual relationship only with the lender not the borrower. The Fund will have the right to receive payments of principal, interest and any fees to which it is entitled only from the lender selling the participation and only upon receipt by the lender of the payments from

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the borrower. Many such loans are secured, although some may be unsecured. Such loans may be in default at the time of purchase. Loans that are fully secured offer the Fund more protection than an unsecured loan in the event of non-payment of scheduled interest or principal. However, there is no assurance that the liquidation of collateral from a secured loan would satisfy the corporate borrower's obligation, or that the collateral can be liquidated. Direct debt instruments may involve a risk of loss in case of default or insolvency of the borrower and may offer less legal protection to the Fund in the event of fraud or misrepresentation. In addition, loan participations involve a risk of insolvency of the lending bank or other financial intermediary. The markets in loans are not regulated by federal securities laws or the Securities and Exchange Commission (the "Commission").

As in the case of other high yield investments, such corporate loans may be rated in the lower rating categories of the established rating services (Ba or lower by Moody's or BB or lower by Standard & Poor's), or may be unrated investments considered by Calamos to be of comparable quality. As in the case of other high yield investments, such corporate loans can be expected to provide higher yields than lower yielding, higher rated fixed income securities, but may be subject to greater risk of loss of principal and income. There are, however, some significant differences between corporate loans and high yield bonds. Corporate loan obligations are frequently secured by pledges of liens and security interests in the assets of the borrower, and the holders of corporate loans are frequently the beneficiaries of debt service subordination provisions imposed on the borrower's bondholders. These arrangements are designed to give corporate loan investors preferential treatment over high yield investors in the event of a deterioration in the credit quality of the issuer. Even when these arrangements exist, however, there can be no assurance that the borrowers of the corporate loans will repay principal and/or pay interest in full. Corporate loans generally bear interest at rates set at a margin above a generally recognized base lending rate that may fluctuate on a day-to-day basis, in the case of the prime rate of a U.S. bank, or which may be adjusted on set dates, typically 30 days but generally not more than one year, in the case of the London Interbank Offered Rate. Consequently, the value of corporate loans held by the Fund may be expected to fluctuate significantly less than the value of other fixed rate high yield instruments as a result of changes in the interest rate environment. On the other hand, the secondary dealer market for certain corporate loans may not be as well developed as the secondary dealer market for high yield bonds, and therefore presents increased market risk relating to liquidity and pricing concerns.

SYNTHETIC FOREIGN MONEY MARKET POSITIONS. The Fund may invest in money market instruments denominated in foreign currencies. In addition to, or in lieu of, such direct investment, the Fund may construct a synthetic foreign money market position by (a) purchasing a money market instrument denominated in one currency, generally U.S. dollars, and (b) concurrently entering into a forward contract to deliver a corresponding amount of that currency in exchange for a different currency on a future date and at a specified rate of exchange. For example, a synthetic money market position in Japanese yen could be constructed by purchasing a U.S. dollar money market instrument, and entering concurrently into a forward contract to deliver a corresponding amount of U.S. dollars in exchange for Japanese yen on a specified date and at a specified rate of exchange. Because of the availability of a variety of highly liquid short-term U.S. dollar money market instruments, a synthetic money market position utilizing such U.S. dollar instruments may offer greater liquidity than direct investment in foreign currency and a concurrent construction of a synthetic position in such foreign currency, in terms of both income yield and gain or loss from changes in currency exchange rates, in general should be similar, but would not be identical because the components of the alternative investments would not be identical.

DEBT OBLIGATIONS OF NON-U.S. GOVERNMENTS. An investment in debt obligations of non-U.S. governments and their political subdivisions (sovereign debt) involves special risks that are not present in corporate debt obligations. The non-U.S. issuer of the sovereign debt or the non-U.S. governmental authorities that control the repayment of the debt may be unable or unwilling to repay principal or interest

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when due, and the Fund may have limited recourse in the event of a default. During periods of economic uncertainty, the market prices of sovereign debt may be more volatile than prices of debt obligations of U.S. issuers. In the past, certain non-U.S. countries have encountered difficulties in servicing their debt obligations, withheld payments of principal and interest and declared moratoria on the payment of principal and interest on their sovereign debt.

A sovereign debtor's willingness or ability to repay principal and pay interest in a timely manner may be affected by, among other factors, its cash flow situation, the extent of its foreign currency reserves, the availability of sufficient non-U.S. currency, the relative size of the debt service burden, the sovereign debtor's policy toward its principal international lenders and local political constraints.

Sovereign debtors may also be dependent on expected disbursements from non-U.S. governments, multilateral agencies and other entities to reduce principal and interest arrearages on their debt. The failure of a sovereign debtor to implement economic reforms, achieve specified levels of economic performance or repay principal or interest when due may result in the cancellation of third-party commitments to lend funds to the sovereign debtor, which may further impair such debtor's ability or willingness to service its debts.

EURODOLLAR INSTRUMENTS AND SAMURAI AND YANKEE BONDS. The Fund may invest in Eurodollar instruments and Samurai and Yankee bonds. Eurodollar instruments are bonds of corporate and government issuers that pay interest and principal in U.S. dollars but are issued in markets outside the United States, primarily in Europe. Samurai bonds are yen-denominated bonds sold in Japan by non-Japanese issuers. Yankee bonds are U.S. dollar-denominated bonds typically issued in the U.S. by non-U.S. governments and their agencies and non-U.S. banks and corporations. The Fund may also invest in Eurodollar Certificates of Deposit ("ECDs"), Eurodollar Time Deposits ("ETDs") and Yankee Certificates of Deposit ("Yankee CDs"). ECDs are U.S. dollar-denominated certificates of deposit issued by non-U.S. branches of domestic banks; ETDs are U.S. dollar-denominated deposits in a non-U.S. branch of a U.S. bank or in a non-U.S. bank; and Yankee CDs are U.S. dollar-denominated certificates of deposit issued by a U.S. branch of a non-U.S. bank and held in the U.S. These investments involve risks that are different from investments in securities issued by U.S. issuers, including potential unfavorable political and economic developments, non-U.S. withholding or other taxes, seizure of non-U.S. deposits, currency controls, interest limitations or other governmental restrictions that might affect payment of principal or interest.

CONVERTIBLE SECURITIES. Convertible securities include any corporate debt security or preferred stock that may be converted into underlying shares of common stock. The common stock underlying convertible securities may be issued by a different entity than the issuer of the convertible securities. Convertible securities entitle the holder to receive interest payments paid on corporate debt securities or the dividend preference on a preferred stock until such time as the convertible security matures or is redeemed or until the holder elects to exercise the conversion privilege. As a result of the conversion feature, however, the interest rate or dividend preference on a convertible security is generally less than would be the case if the securities were issued in non-convertible form.

The value of convertible securities is influenced by both the yield of non-convertible securities of comparable issuers and by the value of the underlying common stock. The value of a convertible security viewed without regard to its conversion feature (i.e., strictly on the basis of its yield) is sometimes referred to as its "investment value." The investment value of the convertible security typically will fluctuate inversely with changes in prevailing interest rates. However, at the same time, the convertible security will be influenced by its "conversion value," which is the market value of the underlying common stock that would be obtained if the convertible security were converted. Conversion value fluctuates directly with the price of the underlying common stock.

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If, because of a low price of the common stock, the conversion value is substantially below the investment value of the convertible security, the price of the convertible security is governed principally by its investment value. If the conversion value of a convertible security increases to a point that approximates or exceeds its investment value, the value of the security will be principally influenced by its conversion value. A convertible security will sell at a premium over its conversion value to the extent investors place value on the right to acquire the underlying common stock while holding a fixed income security. Holders of convertible securities have a claim on the assets of the issuer prior to the common stockholders, but may be subordinated to holders of similar non-convertible securities of the same issuer.

SYNTHETIC CONVERTIBLE INSTRUMENTS. Calamos may establish a "synthetic" convertible instrument by combining fixed income securities with the right to acquire equity securities. In establishing a synthetic instrument, the Fund may pool a basket of fixed-income securities and a basket of warrants or options that produce the economic characteristics similar to a convertible security. Within each basket of fixed-income securities and warrants or options, different companies may issue the fixed-income and convertible components, which may be purchased separately and at different times.

More flexibility is possible in the assembly of a synthetic convertible instrument than in the purchase of a convertible security. Although synthetic convertible instruments may be selected where the two components are issued by a single issuer, thus making the synthetic convertible instrument similar to the true convertible security, the character of a synthetic convertible instrument allows the combination of components representing distinct issuers when Calamos believes that such a combination would better promote the Fund's investment objective. A synthetic convertible instrument also is a more flexible investment in that its two components may be purchased separately. For example, the Fund may purchase a warrant for inclusion in a synthetic convertible instrument but temporarily hold short-term investments while postponing the purchase of a corresponding bond pending development of more favorable market conditions.

A holder of a synthetic convertible instrument faces the risk of a decline in the price of the instrument or the level of the index involved in the convertible component, causing a decline in the value of the call option or warrant purchased to create the synthetic convertible instrument. Should the price of the stock fall below the exercise price and remain there throughout the exercise period, the entire amount paid for the call option or warrant would be lost. Because a synthetic convertible instrument includes the fixed-income component as well, the holder of a synthetic convertible instrument also faces the risk that interest rates will rise, causing a decline in the value of the fixed-income instrument.

The Fund may also purchase synthetic convertible instruments manufactured by other parties, including convertible structured notes. Convertible structured notes are fixed income debentures linked to equity, and are typically issued by investment banks. Convertible structured notes have the attributes of a convertible security, however, the investment bank that issued the convertible note assumes the credit risk associated with the investment, rather than the issuer of the underlying common stock into which the note is convertible.

LENDING OF PORTFOLIO SECURITIES. The Fund may lend its portfolio securities to broker-dealers and banks. Any such loan must be continuously secured by collateral in cash or cash equivalents maintained on a current basis in an amount at least equal to the market value of the securities loaned by the Fund. The Fund would continue to receive the equivalent of the interest or dividends paid by the issuer on the securities loaned, and would also receive an additional return that may be in the form of a fixed fee or a percentage of the collateral. The Fund may pay reasonable fees to persons unaffiliated with the Fund for services in arranging these loans. The Fund would have the right to call the loan and obtain the securities loaned at any time on notice of not more than five business days. The Fund would not have the right to vote the securities during the existence of the loan but would call the loan to permit voting of the securities, if, in Calamos' judgment, a material event requiring a shareholder vote would otherwise occur before the loan was repaid. In the event of bankruptcy or other default of the borrower, the Fund could experience both delays in liquidating the loan collateral or recovering the loaned securities and losses, including (a) possible decline in the value of the collateral or in the value of the securities loaned

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during the period while the Fund seeks to enforce its rights thereto, (b) possible subnormal levels of income and lack of access to income during this period, and (c) expenses of enforcing its rights. In an effort to reduce these risks, Calamos will monitor the creditworthiness of the firms to which the Fund lends securities.

OPTIONS ON SECURITIES, INDEXES AND CURRENCIES. The Fund may seek to generate income from option premiums by writing (selling) options (with an aggregate notional value of up to 33% of the value of the Fund's managed assets). The Fund may write (sell) call options (i) on a portion of the equity securities (including securities that are convertible into equity securities) in the Fund's portfolio and (ii) on broad-based securities indices (such as the S&P 500 or MSCI EAFE) or certain ETFs (exchange traded funds) that trade like common stocks but seek to replicate such market indices. The Fund may also write (sell) both put and call options on certain of the equity securities (including securities that are convertible into equity securities) in the Fund's portfolio where the Fund will own an equity security and simultaneously, write call options and write put options on that security. This strategy may produce a considerably higher return than solely writing call options, but involves a higher degree of risk and potential volatility.

Calamos may also utilize covered put option collars, in which the Fund purchases a put option and simultaneously sells a put option on the same security at a different strike price. The put option collars in which the Fund will invest are sometimes referred to as debit spreads and credit spreads (including strike spreads and time spreads). When the Fund engages in debit spreads the Fund will pay a higher premium for the put option it purchases than it receives for the put option it writes. In so doing, the Fund hopes to realize current gains from favorable market price movements in relation to the exercise price of the option it holds. The Fund's maximum potential profit would be equal to the difference between the two exercise prices, less the net premium paid. When the Fund engages in credit spreads the Fund will receive more in premiums for the option it writes than it will pay for the option it purchases. In so doing, the Fund hopes to realize current gains in the form of premiums. The Fund's maximum potential profit would be equal to the net premium received for the spread. The Fund's maximum potential loss would be limited to the difference between the two exercise prices, less the net premium received.

In addition, to seek to offset some of the risk of a large potential decline in the event the overall stock market has a sizeable short-term or intermediate-term decline, the Fund may also, to a limited extent (with an aggregate notional value of not more than 5% of the value of the Fund's managed assets) purchase put options on broad-based securities indices (such as the S&P 500 or MSCI EAFE) or certain ETFs (exchange traded funds) that trade like common stocks but seek to replicate such market indices.

The Fund may also purchase and sell put options and call options on foreign currencies. The Fund may purchase agreements, sometimes called cash puts, that may accompany the purchase of a new issue of bonds from a dealer.

A put option gives the purchaser of the option, upon payment of a premium, the right to sell, and the writer the obligation to buy, the underlying security, commodity, index, currency or other instrument at the exercise price. For instance, the Fund's purchase of a put option on a security might be designed to protect its holdings in the underlying instrument (or, in some cases, a similar instrument) against a substantial decline in the market value by giving the Fund the right to sell such instrument at the option exercise price. A call option, upon payment of a premium, gives the purchaser of the option the right to buy, and the seller the obligation to sell, the underlying instrument at the exercise price. The Fund's purchase of a call option on a security, financial future, index, currency or other instrument might be intended to protect a fund against an increase in the price of the underlying instrument that it intends to purchase in the future by fixing the price at which it may purchase such instrument.

The Fund is authorized to purchase and sell exchange listed options and over-the-counter options ("OTC options"). Exchange listed options are issued by a regulated intermediary such as the Options Clearing Corporation ("OCC"), which guarantees the performance of the obligations of the parties to such options. In addition, the Fund may purchase instruments structured by broker-dealers or investment banks that package or possess economic characteristics of options. The discussion below uses the OCC as an example, but is also applicable to other financial intermediaries.

With certain exceptions, OCC issued and exchange listed options generally settle by physical delivery of the underlying security or currency, although in the future cash settlement may become available. Index options and Eurodollar instruments are cash settled for the net amount, if any, by which the option is "in-the-money" (i.e., where the value of the underlying instrument exceeds, in the case of a call option, or is less than, in the case of a put option, the exercise price of the option) at the time the option is exercised. Frequently, rather than taking or making delivery of the underlying instrument through the process of exercising the option, listed options are closed by entering into offsetting purchase or sale transactions that do not result in ownership of the new option.

OTC options are purchased from or sold to securities dealers, financial institutions or other parties ("Counterparties") through direct bilateral agreement with the Counterparty. In contrast to exchange listed options, which generally have standardized terms and performance mechanics, all the terms of an OTC option, including such terms as method of settlement, term, exercise price, premium, guarantees and security, are set by negotiation of the parties. The Fund may sell OTC options (other than OTC currency options) that are subject to a buy-back provision permitting the Fund to require the Counterparty to sell the option back to a fund at a formula price within seven days. The Fund expects generally to enter into OTC options that have cash settlement provisions, although it is not required to do so. The staff of the Commission currently takes the position that OTC options purchased by a fund, and portfolio securities "covering" the amount of a fund's obligation pursuant to an OTC option sold by it (or the amount of assets equal to the formula price for the repurchase of the option, if any, less the amount by which the option is in the money) are illiquid.

The Fund may also purchase and sell options on securities indices and other financial indices. Options on securities indices and other financial indices are similar to options on a security or other instrument except that, rather than settling by physical delivery of the underlying instrument, they settle by cash settlement, i.e., an option or an index gives the holder the right to receive, upon exercise of the option, an amount of cash if the closing level of the index upon which the option is based exceeds, in the

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case of a call, or is less than, in the case of a put, the exercise price of the option (except if, in the case of an OTC option, physical delivery is specified). This amount of cash is equal to the excess of the closing price of the index over the exercise price of the option, which also may be multiplied by a formula value. The seller of the option is obligated, in return for the premium received, to make delivery of this amount. The gain or loss on an option on an index depends on price movements in the instruments making upon the market, market segment, industry or other composite on which the underlying index is based, rather than price movements in individual securities, as is the case with respect to options on securities.

The Fund will write call options and put options only if they are "covered." For example, a call option written by the Fund will require the Fund to hold the securities subject to the call (or securities convertible into the needed securities without additional consideration) or to segregate cash or liquid assets sufficient to purchase and deliver the securities if the call is exercised. A call option sold by a fund on an index will require the Fund to own portfolio securities that correlate with the index or to segregate cash or liquid assets equal to the excess of the index value over the exercise price on a current basis. A put option written by the Fund requires the Fund to segregate cash or liquid assets equal to the exercise price.

OTC options entered into by the Fund will generally provide for cash settlement. As a result, when the Fund sells these instruments, it will only segregate an amount of cash or liquid assets equal to its accrued net obligations, as there is no requirement for payment or delivery of amounts in excess of the net amount. These amounts will equal 100% of the exercise price in the case of a non cash-settled put, the same as an OCC guaranteed listed option sold by the Fund, or the in-the-money amount plus any sell-back formula amount in the case of a cash-settled put or call. In addition, when the Fund sells a call option on an index at a time when the in-the-money amount exceeds the exercise price, the Fund will segregate, until the option expires or is closed out, cash or cash equivalents equal in value to such excess. OTC options other than those above may also settle with physical delivery, or with an election of either physical delivery or cash settlement and the Fund will segregate an amount of cash or liquid assets equal to the full value of the option. OTC options settling with physical delivery, or with an election of either physical delivery or cash settlement, will be treated the same as other options settling with physical delivery.

If an option written by the Fund expires, the Fund realizes a capital gain equal to the premium received at the time the option was written. If an option purchased by the Fund expires, the Fund realizes a capital loss equal to the premium paid.

The Fund will realize a capital gain from a closing purchase transaction if the cost of the closing option is less than the premium received from writing the option, or, if it is more, the Fund will realize a capital loss. If the premium received from a closing sale transaction is more than the premium paid to purchase the option, the Fund will realize a capital gain or, if it is less, the Fund will realize a capital loss. The principal factors affecting the market value of a put or a call option include supply and demand, interest rates, the current market price of the underlying security or index in relation to the exercise price of the option, the volatility of the underlying security or index, and the time remaining until the expiration date.

A put or call option purchased by the Fund is an asset of the Fund, valued initially at the premium paid for the option. The premium received for an option written by the Fund is recorded as a deferred credit. The value of an option purchased or written is marked-to-market daily and is valued at the closing price on the exchange on which it is traded or, if not traded on an exchange or no closing price is available, at the mean between the last bid and asked prices.

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RISKS ASSOCIATED WITH OPTIONS. There are several risks associated with transactions in options. For example, there are significant differences between the securities markets, the currency markets and the options markets that could result in an imperfect correlation among these markets, causing a given transaction not to achieve its objectives. A decision as to whether, when and how to use options involves the exercise of skill and judgment, and even a well-conceived transaction may be unsuccessful to some degree because of market behavior or unexpected events. The ability of the Fund to utilize options successfully will depend on Calamos' ability to predict pertinent market investments, which cannot be assured.

The Fund's ability to close out its position as a purchaser or seller of an OCC or exchange listed put or call option is dependent, in part, upon the liquidity of the option market. Among the possible reasons for the absence of a liquid option market on an exchange are: (i) insufficient trading interest in certain options; (ii) restrictions on transactions imposed by an exchange; (iii) trading halts, suspensions or other restrictions imposed with respect to particular classes or series of options or underlying securities including reaching daily price limits; (iv) interruption of the normal operations of the OCC or an exchange; (v) inadequacy of the facilities of an exchange or OCC to handle current trading volume; or (vi) a decision by one or more exchanges to discontinue the trading of options (or a particular class or series of options), in which event the relevant market for that option on that exchange would cease to exist, although outstanding options on that exchange would generally continue to be exercisable in accordance with their terms. If the Fund were unable to close out an option that it has purchased on a security, it would have to exercise the option in order to realize any profit or the option would expire and become worthless. If the Fund were unable to close out a covered call option that it had written on a security, it would not be able to sell the underlying security until the option expired. As the writer of a covered call option on a security, the Fund foregoes, during the option's life, the opportunity to profit from increases in the market value of the security covering the call option above the sum of the premium and the exercise price of the call. As the writer of a covered call option on a foreign currency, the Fund foregoes, during the option's life, the opportunity to profit from currency appreciation.

The hours of trading for listed options may not coincide with the hours during which the underlying financial instruments are traded. To the extent that the option markets close before the markets for the underlying financial instruments, significant price and rate movements can take place in the underlying markets that cannot be reflected in the option markets until the next trading day.

Unless the parties provide for it, there is no central clearing or guaranty function in an OTC option. As a result, if the Counterparty (as described above under "Options on Securities, Indexes and Currencies") fails to make or take delivery of the security, currency or other instrument underlying an OTC option it has entered into with a fund or fails to make a cash settlement payment due in accordance with the terms of that option, a fund will lose any premium it paid for the option as well as any anticipated benefit of the transaction. Accordingly, Calamos must assess the creditworthiness of each such Counterparty or any guarantor or credit enhancement of the Counterparty's credit to determine the likelihood that the terms of the OTC option will be satisfied. The Fund will engage in OTC option transactions only with U.S. government securities dealers recognized by the Federal Reserve Bank of New York as "primary dealers" or broker/dealers, domestic or foreign banks or other financial institutions that have received (or the guarantors of the obligation of which have received) a short-term credit rating of A-1 from S&P or P-1 from Moody's or an equivalent rating from any nationally recognized statistical rating organization ("NRSRO") or, in the case of OTC currency transactions, are determined to be of equivalent credit quality by Calamos.

The Fund may purchase and sell call options on securities indices and currencies. All calls sold by the Fund must be "covered." Even though the Fund will receive the option premium to help protect it against loss, a call sold by the Fund exposes the Fund during the term of the option to possible loss of

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opportunity to realize appreciation in the market price of the underlying security or instrument and may require a fund to hold a security or instrument that it might otherwise have sold. The Fund may purchase and sell put options on securities indices and currencies. In selling put options, there is a risk that the Fund may be required to buy the underlying security at a disadvantageous price above the market price.

FUTURES CONTRACTS AND OPTIONS ON FUTURES CONTRACTS. The Fund may use interest rate futures contracts, index futures contracts and foreign currency futures contracts. An interest rate, index or foreign currency futures contract provides for the future sale by one party and purchase by another party of a specified quantity of a financial instrument or the cash value of an index(1) at a specified price and time. A public market exists in futures contracts covering a number of indexes (including, but not limited to: the Standard & Poor's 500 Index, the Russell 2000 Index, the Value Line Composite Index, and the New York Stock Exchange Composite Index) as well as financial instruments (including, but not limited to: U.S. Treasury bonds, U.S. Treasury notes, Eurodollar certificates of deposit and foreign currencies). Other index and financial instrument futures contracts are available and it is expected that additional futures contracts will be developed and traded.

The Fund may purchase and write call and put futures options. Futures options possess many of the same characteristics as options on securities, indexes and foreign currencies (discussed above). A futures option gives the holder the right, in return for the premium paid, to assume a long position
(call) or short position (put) in a futures contract at a specified exercise price at any time during the period of the option. Upon exercise of a call option, the holder acquires a long position in the futures contract and the writer is assigned the opposite short position. In the case of a put option, the opposite is true. The Fund might, for example, use futures contracts to hedge against or gain exposure to fluctuations in the general level of stock prices, anticipated changes in interest rates or currency fluctuations that might adversely affect either the value of the Fund's securities or the price of the securities that the Fund intends to purchase. Although other techniques could be used to reduce or increase the Fund's exposure to stock price, interest rate and currency fluctuations, the Fund may be able to achieve its desired exposure more effectively and perhaps at a lower cost by using futures contracts and futures options.

The Fund will only enter into futures contracts and futures options that are standardized and traded on an exchange, board of trade or similar entity, or quoted on an automated quotation system.

The success of any futures transaction depends on the investment manager correctly predicting changes in the level and direction of stock prices, interest rates, currency exchange rates and other factors. Should those predictions be incorrect, the Fund's return might have been better had the transaction not been attempted; however, in the absence of the ability to use futures contracts, the investment manager might have taken portfolio actions in anticipation of the same market movements with similar investment results, but, presumably, at greater transaction costs.

When a purchase or sale of a futures contract is made by the Fund, the Fund is required to deposit with its custodian (or broker, if legally permitted) a specified amount of cash or U.S. Government securities or other securities acceptable to the broker ("initial margin"). The margin required for a futures contract is set by the exchange on which the contract is traded and may be modified during the term of the contract, although the Fund's broker may require


(1) A futures contract on an index is an agreement pursuant to which two parties agree to take or make delivery of an amount of cash equal to the difference between the value of the index at the close of the last trading day of the contract and the price at which the index contract was originally written. Although the value of a securities index is a function of the value of certain specified securities, no physical delivery of those securities is made.

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margin deposits in excess of the minimum required by the exchange. The initial margin is in the nature of a performance bond or good faith deposit on the futures contract, which is returned to the Fund upon termination of the contract, assuming all contractual obligations have been satisfied. The Fund expects to earn interest income on its initial margin deposits. A futures contract held by the Fund is valued daily at the official settlement price of the exchange on which it is traded. Each day the Fund pays or receives cash, called "variation margin," equal to the daily change in value of the futures contract. This process is known as "marking-to-market." Variation margin paid or received by the Fund does not represent a borrowing or loan by the Fund but is instead settlement between the Fund and the broker of the amount one would owe the other if the futures contract had expired at the close of the previous day. In computing daily net asset value, the Fund will mark-to-market its open futures positions.

The Fund is also required to deposit and maintain margin with respect to put and call options on futures contracts written by it. Such margin deposits will vary depending on the nature of the underlying futures contract (and the related initial margin requirements), the current market value of the option and other futures positions held by the Fund.

Although some futures contracts call for making or taking delivery of the underlying securities, usually these obligations are closed out prior to delivery by offsetting purchases or sales of matching futures contracts (same exchange, underlying security or index, and delivery month). If an offsetting purchase price is less than the original sale price, the Fund engaging in the transaction realizes a capital gain, or if it is more, the Fund realizes a capital loss. Conversely, if an offsetting sale price is more than the original purchase price, the Fund engaging in the transaction realizes a capital gain, or if it is less, the Fund realizes a capital loss. The transaction costs must also be included in these calculations.

RISKS ASSOCIATED WITH FUTURES. There are several risks associated with the use of futures contracts and futures options. A purchase or sale of a futures contract may result in losses in excess of the amount invested in the futures contract. In trying to increase or reduce market exposure, there can be no guarantee that there will be a correlation between price movements in the futures contract and in the portfolio exposure sought. In addition, there are significant differences between the securities and futures markets that could result in an imperfect correlation between the markets, causing a given transaction not to achieve its objectives. The degree of imperfection of correlation depends on circumstances such as: variations in speculative market demand for futures, futures options and the related securities, including technical influences in futures and futures options trading and differences between the securities markets and the securities underlying the standard contracts available for trading. For example, in the case of index futures contracts, the composition of the index, including the issuers and the weighing of each issue, may differ from the composition of the Fund's portfolio, and, in the case of interest rate futures contracts, the interest rate levels, maturities and creditworthiness of the issues underlying the futures contract may differ from the financial instruments held in the Fund's portfolio. A decision as to whether, when and how to use futures contracts involves the exercise of skill and judgment, and even a well-conceived transaction may be unsuccessful to some degree because of market behavior or unexpected stock price or interest rate trends.

Futures exchanges may limit the amount of fluctuation permitted in certain futures contract prices during a single trading day. The daily limit establishes the maximum amount that the price of a futures contract may vary either up or down from the previous day's settlement price at the end of the current trading session. Once the daily limit has been reached in a futures contract subject to the limit, no more trades may be made on that day at a price beyond that limit. The daily limit governs only price movements during a particular trading day and therefore does not limit potential losses because the limit may work to prevent the liquidation of unfavorable positions. For example, futures prices have occasionally moved to the daily limit for several consecutive trading days with little or no trading, thereby preventing prompt liquidation of positions and subjecting some holders of futures contracts to substantial losses. Stock index futures contracts are not normally subject to such daily price change limitations.

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There can be no assurance that a liquid market will exist at a time when the Fund seeks to close out a futures or futures option position. The Fund would be exposed to possible loss on the position during the interval of inability to close, and would continue to be required to meet margin requirements until the position is closed. In addition, many of the contracts discussed above are relatively new instruments without a significant trading history. As a result, there can be no assurance that an active secondary market will develop or continue to exist.

LIMITATIONS ON OPTIONS AND FUTURES. If other options, futures contracts or futures options of types other than those described herein are traded in the future, the Fund may also use those investment vehicles, provided the Board of Trustees determines that their use is consistent with the Fund's investment objective.

When purchasing a futures contract or writing a put option on a futures contract, the Fund must maintain with its custodian (or broker, if legally permitted) cash or cash equivalents (including any margin) equal to the market value of such contract. When writing a call option on a futures contract, the Fund similarly will maintain with its custodian cash or cash equivalents (including any margin) equal to the amount by which such option is in-the-money until the option expires or is closed by the Fund.

The Fund may not maintain open short positions in futures contracts, call options written on futures contracts or call options written on indexes if, in the aggregate, the market value of all such open positions exceeds the current value of the securities in its portfolio, plus or minus unrealized gains and losses on the open positions, adjusted for the historical relative volatility of the relationship between the portfolio and the positions. For this purpose, to the extent the Fund has written call options on specific securities in its portfolio, the value of those securities will be deducted from the current market value of the securities portfolio.

In order to comply with Commodity Futures Trading Commission ("CFTC") Regulation 4.5 and thereby avoid being deemed a "commodity pool operator," a Fund may use commodity futures or commodity options contracts for either risk management or speculative purposes without any limitation on the notional value of such positions. The Fund has qualified for an exemption from registration as a "commodity pool operator" pursuant to CFTC Regulation 4.5 and, therefore, is not subject to registration or regulation under the Commodity Exchange Act, as amended.

WARRANTS. The Fund may invest in warrants. A warrant is a right to purchase common stock at a specific price (usually at a premium above the market value of the underlying common stock at time of issuance) during a specified period of time. A warrant may have a life ranging from less than a year to twenty years or longer, but a warrant becomes worthless unless it is exercised or sold before expiration. In addition, if the market price of the common stock does not exceed the warrant's exercise price during the life of the warrant, the warrant will expire worthless. Warrants have no voting rights, pay no dividends and have no rights with respect to the assets of the corporation issuing them. The percentage increase or decrease in the value of a warrant may be greater than the percentage increase or decrease in the value of the underlying common stock.

PORTFOLIO TURNOVER. Although the Fund does not purchase securities with a view to rapid turnover, there are no limitations on the length of time that portfolio securities must be held. Portfolio turnover can occur for a number of reasons, including calls for redemption, general conditions in the securities markets, more favorable investment opportunities in other securities, or other factors relating to the desirability of holding or changing a portfolio investment. The portfolio turnover rates may vary greatly from year to year. A high rate of portfolio turnover in the Fund would result in increased transaction expense, which must be borne by that Fund. High portfolio turnover may also result in the realization of capital gains or losses and, to the extent net short-term capital gains are realized, any distributions resulting from such gains will be considered ordinary income for federal income tax purposes.

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SHORT SALES. The Fund may from time to time sell securities short to enhance income and protect against market risk by hedging a portion of the equity risk inherent in the Fund's portfolio. A short sale is effected when Calamos believes that the price of a security will decline, and involves the sale of securities that the Fund does not own, in the hope of purchasing the same securities at a later date at a lower price. There can be no assurance that the Fund will be able to close out a short position (i.e., purchase the same securities) at any particular time or at an acceptable or advantageous price. To make delivery to the buyer, the Fund must borrow the securities from a broker-dealer through which the short sale is executed, and the broker-dealer delivers the securities, on behalf of the Fund, to the buyer. The broker-dealer is entitled to retain the proceeds from the short sale until the Fund delivers to it the securities sold short. In addition, a Fund is required to pay to the broker-dealer the amount of any dividends or interest paid on the securities sold short.

To secure its obligation to deliver to the broker-dealer the securities sold short, the Fund must segregate an amount of cash or liquid securities with its custodian equal to any excess of the current market value of the securities sold short over any cash or liquid securities deposited as collateral with the broker in connection with the short sale (not including the proceeds of the short sale). As a result of that requirement, the Fund will not gain any leverage merely by selling short, except to the extent that it earns interest or other income or gains on the segregated cash or liquid securities while also being subject to the possibility of gain or loss from the securities sold short.

The Fund is said to have a short position in the securities sold until it delivers to the broker-dealer the securities sold, at which time the Fund receives the proceeds of the short sale. The Fund will normally close out a short position by purchasing on the open market and delivering to the broker-dealer an equal amount of the securities sold short.

The Fund will realize a gain if the price of the securities declines between the date of the short sale and the date on which the Fund purchases securities to replace the borrowed securities. On the other hand, a Fund will incur a loss if the price of the securities increases between those dates. The amount of any gain will be decreased and the amount of any loss increased by any premium or interest that the Fund may be required to pay in connection with the short sale. It should be noted that possible losses from short sales differ from those that could arise from a cash investment in a security in that losses from a short sale may be limitless, while the losses from a cash investment in a security cannot exceed the total amount of the investment in the security.

There is also a risk that securities borrowed by the Fund and delivered to the buyer of the securities sold short will need to be returned to the broker-dealer on short notice. If the request for the return of securities occurs at a time when other short sellers of the security are receiving similar requests, a "short squeeze" can occur, meaning that the Fund might be compelled, at the most disadvantageous time, to replace the borrowed securities with securities purchased on the open market, possibly at prices significantly in excess of the proceeds received earlier.

Rule 10a-1 under the Securities Exchange Act of 1934 provides that exchange-traded securities can be sold short only at a price that is higher than the last trade or the same as the last trade price if that price is higher than the price of the previous reported trade. The requirements of Rule 10a-1 can delay, or in some cases prevent, execution of short sales, resulting in opportunity costs and increased exposure to market action.

The Fund may also make short sales "against the box," meaning that at all times when a short position is open the Fund owns an equal amount of such securities or securities convertible into or exchangeable, without payment of further consideration, for securities of the same issue as, and in an amount equal to, the securities sold short. Short sales "against the box" result in a "constructive sale" and require the Fund to recognize any taxable gain unless an exception to the constructive sale rule applies.

The Fund will not make a short sale of securities (other than a short sale "against the box"), if more than 20% of its net assets would be deposited with brokers as collateral or allocated to segregated accounts in connection with all outstanding short sales (other than short sales "against the box").

In addition to enabling the Fund to hedge against market risk, short sales may afford the Fund an opportunity to earn additional current income to the extent it is able to enter into arrangements with broker-dealers through which the short sales are executed to receive income with respect to the proceeds of the short sales during the period the Fund's short positions remain open. The Funds believe that some broker-dealers may be willing to enter into such arrangements, but there is no assurance that they will be able to enter into such arrangements to the desired degree.

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SWAPS, CAPS, FLOORS AND COLLARS. The Fund may enter into interest rate, currency, index, credit default and other swaps and the purchase or sale of related caps, floors and collars. The Fund expects to enter into these transactions primarily to preserve a return or spread on a particular investment or portion of its portfolio, to protect against currency fluctuations, as a duration management technique or to protect against any increase in the price of securities the Fund anticipates purchasing at a later date. The Fund will not sell interest rate caps or floors where it does not own securities or other instruments providing the income stream the Fund may be obligated to pay. Interest rate swaps involve the exchange by the Fund with another party of their respective commitments to pay or receive interest, e.g., an exchange of floating rate payments for fixed rate payments with respect to a notional amount of principal. A currency swap is an agreement to exchange cash flows on a notional amount of two or more currencies based on the relative value differential among them and an index swap is an agreement to swap cash flows on a notional amount based on changes in the values of the reference indices. The purchase of a cap entitles the purchaser to receive payments on a notional principal amount from the party selling such cap to the extent that a specified index exceeds a predetermined interest rate or amount. The purchase of a floor entitles the purchaser to receive payments on a notional principal amount from the party selling such floor to the extent that a specified index falls below a predetermined interest rate or amount. A collar is a combination of a cap and a floor that preserves a certain return within a predetermined range of interest rates or values.

The Fund will usually enter into swaps on a net basis, i.e., the two payment streams are netted out in a cash settlement on the payment date or dates specified in the instrument, with the Fund receiving or paying, as the case may be, only the net amount of the two payments. The Fund intends to maintain in a segregated account with its custodian cash or liquid securities having a value at least equal to the Fund's net payment obligations under any swap transaction, marked-to-market daily. Inasmuch as the Fund will segregate assets (or enter into offsetting positions) to cover its obligations under swaps, Calamos and the Fund believe such obligations do not constitute senior securities under the Investment Company Act of 1940 (the "1940 Act") and, accordingly, will not treat them as being subject to its borrowing restrictions.

The Fund will not enter into any swap, cap, floor or collar transaction unless, at the time of entering into such transaction, the Fund believes that the Counterparty has the financial resources to honor its obligation under the transaction. Further, Calamos will continually monitor the financial stability of a Counterparty to a swap or cap transaction in an effort to proactively protect the Fund's investments. If there is a default by the Counterparty, the Fund may have contractual remedies pursuant to the agreements related to the transaction. The use of swaps and caps is a highly specialized activity that involves investment techniques and risks different from those associated with ordinary portfolio security transactions. The Fund's use of swaps or caps could enhance or harm the overall performance on the common shares. For example, to the extent there is a decline in interest rates, the value of the interest rate swap or cap could decline, and could result in a decline in the net asset value of the common shares. In addition, if short-term interest rates are lower than the Fund's fixed rate of payment on the interest rate swap, the swap will reduce common share net earnings. If, on the other hand, short-term interest rates are higher than the fixed rate of payment on the interest rate swap, the swap will enhance common share net earnings. Buying caps could enhance the performance of the common shares by providing a maximum leverage expense. Buying caps could also decrease the net earnings of the common shares in the event that the premium paid by the Fund to the Counterparty exceeds the additional amount the Fund would have been required to pay had it not entered into the cap agreement. The Fund has no current intention of selling swaps or caps.

Swaps and caps do not involve the delivery of securities or other underlying assets or principal. Accordingly, the risk of loss with respect to swaps is limited to the net amount of payments that the Fund is contractually obligated to make. If the Counterparty defaults, the Fund would not be able to use the anticipated net receipts under the swap or cap to offset the payments required of the Fund. Depending on whether the Fund would be entitled to receive net payments from the Counterparty on the swap or cap, such a default could negatively impact the performance of the common shares.

In addition, at the time the swap or cap transaction reaches its scheduled termination date, there is a risk that the Fund would not be able to obtain a replacement transaction or that the terms of the replacement would not be as favorable as on the expiring transaction. If this occurs, it could have a negative impact on the performance of the Fund's common shares.

The Fund may choose or be required to redeem some or all of the preferred shares or prepay any borrowings. This redemption would likely result in the Fund seeking to terminate early all or a portion of any swap or cap transaction. Such early termination of a swap could result in termination payment by or to the Fund. An early termination of a cap could result in a termination payment to the Fund.

The swap market has grown substantially in recent years with a large number of banks and investment banking firms acting both as principals and as agents utilizing standardized swap documentation. As a result, the

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swap market has become relatively liquid, however, some swaps may be considered illiquid. Caps, floors and collars are more recent innovations for which standardized documentation has not yet been fully developed and, accordingly, they are less liquid than swaps.

STRUCTURED PRODUCTS. The Fund may invest in interests in entities organized and operated for the purpose of restructuring the investment characteristics of certain other investments. This type of restructuring involves the deposit with or purchase by an entity, such as a corporation or trust, of specified instruments and the issuance by that entity of one or more classes of securities ("structured products") backed by, or representing interests in, the underlying instruments. The term "structured products" as used herein excludes synthetic convertibles and interest rate transactions. The cash flow on the underlying instruments may be apportioned among the newly issued structured products to create securities with different investment characteristics such as varying maturities, payment priorities and interest rate provisions, and the extent of the payments made with respect to structured products is dependent on the extent of the cash flow on the underlying instruments. The Fund may invest in structured products, which represent derived investment positions based on relationships among different markets or asset classes.

The Fund may also invest in other types of structured products, including, among others, baskets of credit default swaps referencing a portfolio of high-yield securities. A structured product may be considered to be leveraged to the extent its interest rate varies by a magnitude that exceeds the magnitude of the change in the index rate. Because they are linked to their underlying markets or securities, investments in structured products generally are subject to greater volatility than an investment directly in the underlying market or security. Total return on the structured product is derived by linking return to one or more characteristics of the underlying instrument. Because certain structured products of the type in which the Fund may invest may involve no credit enhancement, the credit risk of those structured products generally would be equivalent to that of the underlying instruments. The Fund may invest in a class of structured products that is either subordinated or unsubordinated to the right of payment of another class. Subordinated structured products typically have higher yields and present greater risks than unsubordinated structured products. Although the Fund's purchase of subordinated structured products would have similar economic effect to that of borrowing against the underlying securities, the purchase will not be deemed to be leverage for purposes of the Fund's limitations related to borrowing and leverage.

Certain issuers of structured products may be deemed to be "investment companies" as defined in the 1940 Act. As a result, the Fund's investments in these structured products may be limited by the restrictions contained in the 1940 Act. Structured products are typically sold in private placement transactions, and there currently may be no active trading market for structured products. As a result, certain structured products in which the Fund invests may be deemed illiquid.

"WHEN-ISSUED" AND DELAYED DELIVERY SECURITIES AND REVERSE REPURCHASE

AGREEMENTS. The Fund may purchase securities on a when-issued or delayed-delivery basis. Although the payment and interest terms of these securities are established at the time the Fund enters into the commitment, the securities may be delivered and paid for a month or more after the date of purchase, when their value may have changed. The Fund makes such commitments only with the intention of actually acquiring the securities, but may sell the securities before settlement date if Calamos deems it advisable for investment reasons. The Fund may utilize spot and forward foreign currency exchange transactions to reduce the risk inherent in fluctuations in the exchange rate between one currency and another when securities are purchased or sold on a when-issued or delayed-delivery basis.

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The Fund may enter into reverse repurchase agreements with banks and securities dealers. A reverse repurchase agreement is a repurchase agreement in which the Fund is the seller of, rather than the investor in, securities and agrees to repurchase them at an agreed-upon time and price. Use of a reverse repurchase agreement may be preferable to a regular sale and later repurchase of securities because it avoids certain market risks and transaction costs.

At the time when the Fund enters into a binding obligation to purchase securities on a when-issued basis or enters into a reverse repurchase agreement, liquid assets (cash, U.S. Government securities or other "high-grade" debt obligations) of the Fund having a value at least as great as the purchase price of the securities to be purchased will be segregated on the books of the Fund and held by the custodian throughout the period of the obligation. The use of these investment strategies may increase net asset value fluctuation.

ILLIQUID SECURITIES. The Fund may invest up to 15% of its managed assets in securities that, at the time of investment, are illiquid (determined using the Commission's standard applicable to investment companies, i.e., securities that can not be disposed of within 7 days in the ordinary course of business at approximately the value at which the Fund has valued the securities). The Fund may also invest without limit in securities that have not been registered for public sale, but that are eligible for purchase and sale by certain qualified institutional buyers ("Rule 144A Securities"). Calamos, under the supervision of the Board of Trustees, will determine whether securities purchased under Rule 144A are illiquid (that is, not readily marketable) and thus subject to the Fund's limit on investing in no more than 15% of its managed assets in illiquid securities. Investments in Rule 144A Securities could have the effect of increasing the amount of the Fund's assets invested in illiquid securities if qualified institutional buyers are unwilling to purchase these Rule 144A Securities.

Illiquid securities may be difficult to dispose of at a fair price at the times when the Fund believes it is desirable to do so. The market price of illiquid securities generally is more volatile than that of more liquid securities, which may adversely affect the price that the Fund pays for or recovers upon the sale of illiquid securities. Illiquid securities are also more difficult to value and Calamos' judgment may play a greater role in the valuation process. Investment of the Fund's assets in illiquid securities may restrict the Fund's ability to take advantage of market opportunities. The risks associated with illiquid securities may be particularly acute in situations in which the Fund's operations require cash and could result in the Fund borrowing to meet its short-term needs or incurring losses on the sale of illiquid securities.

The Fund may invest in bonds, corporate loans, convertible securities, preferred stocks and other securities that lack a secondary trading market or are otherwise considered illiquid. Liquidity of a security relates to the ability to easily dispose of the security and the price to be obtained upon disposition of the security, which may be less than would be obtained for a comparable more liquid security. Such investments may affect the Fund's ability to realize the net asset value in the event of a voluntary or involuntary liquidation of its assets.

TEMPORARY DEFENSIVE INVESTMENTS. The Fund may make temporary investments without limitation when Calamos determines that a defensive position is warranted. Such investments may be in money market instruments, consisting of obligations of, or guaranteed as to principal and interest by, the U.S. Government or its agencies or instrumentalities; certificates of deposit, bankers' acceptances and other obligations of domestic banks having total assets of at least $500 million and that are regulated by the U.S. Government, its agencies or instrumentalities; commercial paper rated in the highest category by a recognized rating agency; and repurchase agreements.

REPURCHASE AGREEMENTS. As part of its strategy for the temporary investment of cash, the Fund may enter into "repurchase agreements" with member banks of the Federal Reserve System or primary dealers (as designated by the Federal Reserve Bank of New York) in such securities. A repurchase agreement arises when the Fund purchases a security and simultaneously agrees to resell it to the vendor at an agreed upon future date. The resale price is greater than the purchase price, reflecting an agreed upon market rate of return that is effective for the period of time the Fund holds the security and that is not related to the coupon rate on the purchased security. Such agreements generally have maturities of no more than seven days and could be used to permit the Fund to earn interest on assets awaiting long term investment. The Fund requires continuous maintenance by the custodian for the Fund's account in the

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Federal Reserve/Treasury Book Entry System of collateral in an amount equal to, or in excess of, the market value of the securities that are the subject of a repurchase agreement. Repurchase agreements maturing in more than seven days are considered illiquid securities. In the event of a bankruptcy or other default of a seller of a repurchase agreement, the Fund could experience both delays in liquidating the underlying security and losses, including: (a) possible decline in the value of the underlying security during the period while the Fund seeks to enforce its rights thereto; (b) possible subnormal levels of income and lack of access to income during this period; and (c) expenses of enforcing its rights.

REAL ESTATE INVESTMENT FUNDS ("REITS") AND ASSOCIATED RISK FACTORS. REITs are pooled investment vehicles that invest primarily in income producing real estate or real estate related loans or interests. REITs are generally classified as equity REITs, mortgage REITs or a combination of equity and mortgage REITs. Equity REITs invest the majority of their assets directly in real property and derive income primarily from the collection of rents. Equity REITs can also realize capital gains by selling properties that have appreciated in value. Mortgage REITs invest the majority of their assets in real estate mortgages and derive income from the collection of interest payments. REITs are generally not taxed on income timely distributed to shareholders provided they comply with the applicable requirements of the Code. The Fund will indirectly bear its proportionate share of any management and other expenses paid by REITs in which it invests in addition to the expenses paid by the Fund. Debt securities issued by REITs are, for the most part, general and unsecured obligations and are subject to risks associated with REITs.

Investing in REITs involves certain unique risks in addition to those risks associated with investing in the real estate industry in general. An equity REIT may be affected by changes in the value of the underlying properties owned by the REIT. A mortgage REIT may be affected by changes in interest rates and the ability of the issuers of its portfolio mortgages to repay their obligations. REITs are dependent upon the skills of their managers and are not diversified. REITs are generally dependent upon maintaining cash flows to repay borrowings and to make distributions to shareholders and are subject to the risk of default by lessees or borrowers. REITs whose underlying assets are concentrated in properties used by a particular industry, such as health care, are also subject to risks associated with such industry.

REITs (especially mortgage REITs) are also subject to interest rate risks. When interest rates decline, the value of a REIT's investment in fixed rate obligations can be expected to rise. Conversely, when interest rates rise, the value of a REIT's investment in fixed rate obligations can be expected to decline. If the REIT invests in adjustable rate mortgage loans the interest rates on which are reset periodically, yields on a REIT's investments in such loans will gradually align themselves to reflect changes in market interest rates. This causes the value of such investments to fluctuate less dramatically in response to interest rate fluctuations than would investments in fixed rate obligations.

REITs may have limited financial resources, may trade less frequently and in a limited volume and may be subject to more abrupt or erratic price movements than larger company securities. Historically, REITs have been more volatile in price than the larger capitalization stocks included in Standard & Poor's 500 Stock Index.

REITs are subject to a highly technical and complex set of provisions in the Code. It is possible that the Fund may invest in a real estate company that purports to be a REIT and that the company could fail to qualify as a REIT and as a result, would fail to qualify for tax free pass-through of income under the Code. In the event of any such unexpected failure to qualify as a REIT, the company would be subject to corporate-level taxation, significantly reducing the return to the Fund on its investment in such company. REITs could also possibly fail to maintain their exemptions from registration under the 1940 Act. The above factors may also adversely affect a borrower's or a lessee's ability to meet its obligations to the REIT. In the event of a default by a borrower or lessee, the REIT may experience delays in

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enforcing its rights as a mortgagee or lessor and may incur substantial costs associated with protecting its investments.

OTHER INVESTMENT COMPANIES. The Fund may invest in the securities of other investment companies to the extent that such investments are consistent with the Fund's investment objective and policies and permissible under the 1940 Act. Under the 1940 Act, the Fund may not acquire the securities of other domestic or non-U.S. investment companies if, as a result, (i) more than 10% of the Fund's total assets would be invested in securities of other investment companies, (ii) such purchase would result in more than 3% of the total outstanding voting securities of any one investment company being held by the Fund, or (iii) more than 5% of the Fund's total assets would be invested in any one investment company. These limitations do not apply to the purchase of shares of any investment company in connection with a merger, consolidation, reorganization or acquisition of substantially all the assets of another investment company.

The Fund, as a holder of the securities of other investment companies, will bear its pro rata portion of the other investment companies' expenses, including advisory fees. These expenses are in addition to the direct expenses of the Fund's own operations.

INVESTMENT RESTRICTIONS

The following are the Fund's fundamental investment restrictions. These restrictions may not be changed without the approval of the holders of a majority of the Fund's outstanding voting securities (which for this purpose and under the 1940 Act means the lesser of (i) 67% of the common shares represented at a meeting at which more than 50% of the outstanding common shares are represented or (ii) more than 50% of the outstanding common shares). If the Fund were to issue a class of preferred shares, the investment restrictions could not be changed without the approval of a majority of the outstanding common and preferred shares, voting together as a class, and the approval of a majority of the outstanding preferred shares, voting separately by class.

The Fund may not:

(1) Issue senior securities, except as permitted by the 1940 Act and the rules and interpretive positions of the Commission thereunder.

(2) Borrow money, except as permitted by the 1940 Act and the rules and interpretive positions of the Commission thereunder.

(3) Invest in real estate, except that the Fund may invest in securities of issuers that invest in real estate or interests therein, securities that are secured by real estate or interests therein, securities of real estate investment funds and mortgage-backed securities.

(4) Make loans, except by the purchase of debt obligations, by entering into repurchase agreements or through the lending of portfolio securities and as otherwise permitted by the 1940 Act and the rules and interpretive positions of the Commission thereunder.

(5) Invest in physical commodities or contracts relating to physical commodities.

(6) Act as an underwriter, except as it may be deemed to be an underwriter in a sale of securities held in its portfolio.

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(7) Make any investment inconsistent with the Fund's classification as a diversified investment company under the 1940 Act and the rules and interpretive positions of the Commission thereunder.

(8) Concentrate its investments in securities of companies in any particular industry as defined in the 1940 Act and the rules and interpretive positions of the Commission thereunder.

All other investment policies of the Fund are considered non-fundamental and may be changed by the Board of Trustees without prior approval of the Fund's outstanding voting shares.

Currently under the 1940 Act, the Fund is not permitted to issue preferred shares unless immediately after such issuance the net asset value of the Fund's portfolio is at least 200% of the liquidation value of the outstanding preferred shares (i.e., such liquidation value may not exceed 50% of the value of the Fund's total assets). In addition, currently under the 1940 Act, the Fund is not permitted to declare any cash dividend or other distribution on its common shares unless, at the time of such declaration, the net asset value of the Fund's portfolio (determined after deducting the amount of such dividend or distribution) is at least 200% of such liquidation value. Currently under the 1940 Act, the Fund is not permitted to incur indebtedness unless immediately after such borrowing the Fund has asset coverage of at least 300% of the aggregate outstanding principal balance of indebtedness (i.e., such indebtedness may not exceed 33 1/3% of the value of the Fund's total assets). Additionally, currently under the 1940 Act, the Fund may not declare any dividend or other distribution upon any class of its shares, or purchase any such shares, unless the aggregate indebtedness of the Fund has, at the time of the declaration of any such dividend or distribution or at the time of any such purchase, an asset coverage of at least 300% after deducting the amount of such dividend, distribution, or purchase price, as the case may be.

Currently under the 1940 Act, the Fund is not permitted to lend money or property to any person, directly or indirectly, if such person controls or is under common control with the Fund, except for a loan from the Fund to a company that owns all of the outstanding securities of the Fund, except directors' qualifying shares. Currently, under interpretative positions of the Commission, the Fund may not have on loan at any given time securities representing more than one-third of its total assets.

Currently under the 1940 Act, a "senior security" does not include any promissory note or evidence of indebtedness where such loan is for temporary purposes only and in an amount not exceeding 5% of the value of the total assets of the issuer at the time the loan is made. A loan is presumed to be for temporary purposes if it is repaid within sixty days and is not extended or renewed.

Currently, the Fund would be deemed to "concentrate" in a particular industry if it invested 25% or more of its total assets in that industry. Currently under the 1940 Act, a "diversified company" means a management company that meets the following requirements: at least 75% of the value of its total assets is represented by cash and cash items (including receivables), government securities, securities of other investment companies, and other securities for the purposes of this calculation limited in respect of any one issuer to an amount not greater in value than 5% of the value of the total assets of such management company and not more than 10% of the outstanding voting securities of such issuer.

Under the 1940 Act, the Fund may invest up to 10% of its total assets in the aggregate in shares of other investment companies and up to 5% of its total assets in any one investment company, provided the investment does not represent more than 3% of the voting stock of the acquired investment company at the time such shares are purchased. As a shareholder in any investment company, the Fund will bear its ratable share of that investment company's expenses, and would remain subject to payment of the Fund's advisory fees and other expenses with respect to assets so invested. Holders of common shares

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would therefore be subject to duplicative expenses to the extent the Fund invests in other investment companies. In addition, the securities of other investment companies may also be leveraged and will therefore be subject to the same leverage risks described herein and in the Prospectus. As described in the prospectus in the section entitled "Risk Factors," the net asset value and market value of leveraged shares will be more volatile and the yield to shareholders will tend to fluctuate more than the yield generated by unleveraged shares.
In addition, to comply with U.S. federal income tax requirements for qualification as a "regulated investment company," the Fund's investments will be limited by both an income and an asset diversification test. See "U.S. Federal Income Tax Matters."

As a non-fundamental policy, the Fund may not issue preferred shares, borrow money or issue debt securities in an aggregate amount exceeding 38% of the Fund's total assets.

MANAGEMENT OF THE FUND

TRUSTEES AND OFFICERS. The Fund's Board of Trustees provides broad supervision over the Fund's affairs. The officers of the Fund are responsible for the Fund's operations. The Fund's Trustees and officers are listed below, together with their age, positions held with the Fund, term of office and length of service and principal occupations during the past five years. Asterisks indicates those Trustees who are interested persons of the Fund within the meaning of the 1940 Act, and they are referred to as Interested Trustees. Trustees who are not interested persons of the Fund are referred to as Independent Trustees. Each of the Trustees serves as a Trustee of other investment companies (13 U.S. registered investment portfolios, not including the Fund) for which Calamos serves as investment adviser (collectively, the "Calamos Funds"). The address for all Independent and Interested Trustees and all officers of the Fund is 2020 Calamos Court, Naperville, Illinois 60563.

                                                                          NUMBER OF
                                                     TERM OF OFFICE     PORTFOLIOS IN        PRINCIPAL OCCUPATION DURING PAST FIVE
      NAME AND AGE AT             POSITIONS HELD     AND LENGTH OF       FUND COMPLEX        YEARS AND OTHER DIRECTORSHIPS HELD BY
       MARCH 31, 2005             WITH THE FUND         SERVICE       OVERSEEN BY TRUSTEE                 THE TRUSTEE
----------------------------      -------------     ----------------  -------------------  -----------------------------------------
INTERESTED TRUSTEES:

*John P. Calamos (64)              Trustee and      Trustee since             13           President and CEO, Calamos Asset
                                   President        March 12, 2004.                        Management, Inc. ("CAM"), Calamos
                                                    Term expires                           Holdings, LLC ("CHLLC"); Calamos and
                                                    in 2008.                               its predecessor, and Calamos Financial
                                                                                           Services LLC and its predecessor
                                                                                           ("CFS"); Director, CAM.

*Nick P. Calamos (43)              Trustee and      Trustee since             13           Senior Executive Vice President, CAM,
                                   Vice President   March 12, 2004.                        CHLLC, Calamos and CFS; Director, CAM.
                                                    Term expires
                                                    in 2007.

**Weston W. Marsh (55)             Trustee          Trustee since             13           Partner, Freeborn & Peters (law firm).
                                                    March 12, 2004.
                                                    Term expires
                                                    in 2008.

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                                                                         NUMBER OF
                                                    TERM OF OFFICE     PORTFOLIOS IN       PRINCIPAL OCCUPATION DURING PAST FIVE
     NAME AND AGE AT            POSITIONS HELD      AND LENGTH OF       FUND COMPLEX       YEARS AND OTHER DIRECTORSHIPS HELD BY
      MARCH 31, 2005            WITH THE FUND          SERVICE       OVERSEEN BY TRUSTEE                THE TRUSTEE
-------------------------       --------------     ----------------  -------------------  ----------------------------------------
INDEPENDENT TRUSTEES:

Joe F. Hanauer (68)                Trustee          Trustee since           13            Private investor; Director, MAF Bancorp
                                                    March 12, 2004.                       (banking); Chairman and Director,
                                                    Term expires                          Homestore.com, Inc., (Internet provider of
                                                    in 2006.                              real estate information and products);
                                                                                          Director, Combined Investments, L.P.
                                                                                          (investment management).


John E. Neal (55)                  Trustee          Trustee since           13            Private investor; Managing Director,
                                                    March 12, 2004.                       Bank One Capital Markets, Inc. (investment
                                                    Term expires                          banking) (2000-2004); Executive
                                                    in 2006.                              Vice President and Head of Real Estate
                                                                                          Department, Bank One (1998-2000);
                                                                                          Director, the Brickman Group, Ltd.
                                                                                          (landscaping company).

William R. Rybak (54)              Trustee          Trustee since           13            Private investor; formerly Executive Vice
                                                    March 12, 2004.                       President and CFO, Van Kampen
                                                    Term expires                          Investments, Inc. (investment manager);
                                                    in 2008.                              Director, Howe Barnes Investments
                                                                                          (investment services firm); Director,
                                                                                          PrivateBancorp, Inc. (bank holding
                                                                                          company).

***Stephen B. Timbers (60)         Trustee          Trustee since           13            Private investor; formerly Vice Chairman,
                                                    March 12, 2004.                       Northern Trust Corporation (bank holding
                                                    Term expires in                       company);President and Chief Executive
                                                    2007.                                 Officer, Northern Trust Investments, N.A.
                                                                                          (investment manager) formerly President,
                                                                                          Northern Trust Global Investments, a
                                                                                          division of Northern Trust Corporation and
                                                                                          Executive Vice President, The Northern
                                                                                          Trust Corporation; Trustee, Northern
                                                                                          Mutual Fund Complex**** (registered
                                                                                          investment companies).


* Messrs. John Calamos and Nick Calamos are trustees who are "interested persons" of the Fund as defined in the Investment Company Act of 1940 because they are affiliates of Calamos and CFS. Nick Calamos is a nephew of John Calamos.

** Mr. Marsh is a partner at a law firm that has performed work for a number of underwriters and may be deemed to be an interested person for as long as those underwriters serve as principal underwriters to the Fund. In addition, Mr. Marsh's law firm has performed work for John P. Calamos, the chief executive and a controlling person of Calamos (such work was not with respect to 1940 Act or Investment Advisers Act of 1940 matters). Upon the advice of counsel to the Fund, the Fund does not believe that Mr. Marsh is an "interested person" of Calamos.

*** Mr. Timbers serves as lead Independent Trustee of the board.

**** Overseeing 53 portfolios in fund complex.

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                                                     TERM OF OFFICE         PRINCIPAL OCCUPATION DURING PAST FIVE
       NAME AND AGE AT             POSITIONS HELD    AND LENGTH OF          YEARS AND OTHER DIRECTORSHIPS HELD BY
       MARCH 31, 2005              WITH THE FUND        SERVICE                         THE TRUSTEE
----------------------------       ------------     ----------------      -----------------------------------------
FUND OFFICERS:

Nimish Bhatt (42)                  Treasurer        Since March 12,       Senior Vice President and Director of
                                                    2004. Serves at       Operations, Calamos, CAM, CHLLC and CFS (since 2004);
                                                    the discretion of     Senior Vice President, Alternative Investments
                                                    the Board.            and Tax Services, BISYS (financial services
                                                                          firm) (1996-2004).

Patrick H. Dudasik (50)            Vice President   Since March 12,       Executive Vice President, Chief Financial Officer
                                                    2004. Serves at       and Administrative Officer and Treasurer
                                                    the discretion of     of CAM and CHLLC (since 2004), Calamos and
                                                    the Board.            CFS (since 2001); Chief Financial
                                                                          Officer, David Gomez and Associates, Inc.
                                                                          (executive search firm) (1998-2001); and Chief Financial
                                                                          Officer, Scudder Kemper Investments Inc., prior thereto.

James S. Hamman, Jr. (35)          Secretary        Since March 12,       Executive Vice President, Secretary and General
                                                    2004. Serves at       Counsel, CAM and CHLLC (since 2004), Calamos
                                                    the discretion of     and CFS (since 1998).
                                                    the Board

Moses Kovalchuk (37)               Assistant        Since June 30,        Vice President of Mutual Fund Operations, Calamos
                                   Treasurer        2005. Serves at       (since 2005); Vice  President of Fund
                                                    the discretion        Accounting, J.P. Morgan Chase (2002-2005); Vice
                                                    of the board.         President of Fund Accounting, Deutsche Asset
                                                                          Management (2000-2002).

Kevin S. Woodard (39)              Assistant        Since April 6,        Senior Vice President and Associate General Counsel,
                                   Secretary        2005. Serves at       Calamos (since 2005); Vice President and Counsel,
                                                    the discretion of     Fifth Third Bank (1997-2005).
                                                    the board.



Mark Mickey (53)                   Chief            Since June 30,        Chief Compliance Officer, Calamos (since 2005);
                                   Compliance       2005. Serves at       Director of Risk Assessment and Internal
                                   Officer          the discretion of     Audit, Calamos (2003-2005); President, Mark Mickey
                                                    the board.            Consulting (2002-2003); Executive Vice President and
                                                                          Head of Compliance, ABN AMRO, prior thereto.

The Fund's Board of Trustees consists of seven members. The term of one class expires each year commencing with the first annual meeting following this public offering and no term shall continue for more than three years after the applicable election. The terms of Joe F. Hanauer and John E. Neal expire at the first annual meeting following this public offering, the terms of Nick P. Calamos and Stephen B. Timbers expire at the second annual meeting, and the terms of John P. Calamos, Weston W. Marsh and William Rybak expire at the third annual meeting. Subsequently, each class of Trustees will stand for election at the conclusion of its respective term. Such classification may prevent replacement of a majority of the Trustees for up to a two-year period. Each officer serves until his or her successor is chosen and qualified or until his or her resignation or removal by the Board of Trustees.

COMMITTEES OF THE BOARD OF TRUSTEES. The Fund's Board of Trustees currently has three standing committees. The committees are described below and the members of each committee constitute the entire committee.

Executive Committee. Messrs. John Calamos, Nick Calamos and Stephen Timbers are members of the Executive Committee, which has authority during intervals between meetings of the Board of Trustees to exercise the powers of the Board, with certain exceptions. Both John Calamos and Nick Calamos are Interested Trustees of the Fund.

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Audit Committee. Messrs. Hanauer, Neal, Rybak and Timbers serve on the Audit Committee. The Audit Committee operates under a written charter adopted and approved by the Board. The Audit Committee selects independent auditors, approves services to be rendered by the auditors, monitors the auditors' performance, reviews the results of the Fund's audit, determines whether to recommend to the Board that the Fund's audited financial statements be included in the Fund's annual report and responds to other matters deemed appropriate by the Board of Trustees. All members of the Audit Committee are Independent Trustees of the Fund.

Governance Committee. Messrs. Hanauer, Marsh, Neal, Rybak and Timbers serve on the Governance Committee. The Governance Committee operates under a written charter adopted and approved by the Board. The Governance Committee oversees the independence and effective functioning of the Board of Trustees and endeavors to be informed about good practices for mutual fund boards. The Governance Committee also functions as a nominating committee by making recommendations to the Board of Trustees regarding candidates for election as non-interested Trustees. In making such recommendations, the Governance Committee considers a number of factors, including a candidate's background, integrity, knowledge and relevant experience. These factors are set forth in an appendix to the written charter. Any prospective candidate is interviewed by the Trustees, and references are checked. The Governance Committee does not have a policy to consider shareholder recommendations regarding candidates for election as trustees. The Committee determined that it is appropriate not to have a policy to consider shareholder recommendations because the current process of identifying and recommending potential candidates is sufficient to ensure a knowledgeable and independent Board.

Dividend Committee. Messrs. John Calamos and Nick Calamos serve on the Dividend Committee, which has the authority to declare dividends, capital gains distributions and return of capital distributions on behalf of the Fund. Both John Calamos and Nick Calamos are interested trustees of the Fund.

In addition to the above committees, there is a pricing committee, appointed by the Board of Trustees, comprised of officers of the Fund and employees of Calamos.

During the fiscal year ended October 31, 2004, the Fund's Board of Trustees held 3 meetings, the Executive Committee held no meetings, the Audit Committee held 2 meetings, the Governance Committee held 1 meeting and the Dividend Committee held no meetings. All of the Trustees and committee members then serving attended at least 75% of the meetings of the Board of Trustees and applicable committees held during each such fiscal year.

COMPENSATION OF OFFICERS AND TRUSTEES. The Fund pays no salaries or compensation to any of its officers or to the Trustees who are affiliated persons of Calamos. Although they are compensated, the non-interested Trustees do not receive any pension or retirement benefits from the Fund. The following table sets forth the total compensation paid to each Trustee (including any amounts deferred, as described below) by the Fund and the Calamos Fund Complex as a group. Compensation from the Fund is for the current calendar year and is estimated. Total compensation from the Calamos Fund Complex as a group is for the calendar year ended December 31, 2004.

                                               ESTIMATED AGGREGATE            TOTAL COMPENSATION FROM
         NAME OF TRUSTEE                      COMPENSATION FROM FUND          CALAMOS FUND COMPLEX(1)*
----------------------------------           -----------------------        ---------------------------
John P. Calamos...................                     $           0                     $            0
Nick P. Calamos...................                                 0                                  0
Joe F. Hanauer....................                          1,292.23                             50,000
Weston W. Marsh...................                          1,259.93                             48,750
John E. Neal......................                          1,292.23                             50,000
William Rybak.....................                          1,292.23                             50,000
Stephen B. Timbers................                            982.10                             38,000


(1) Includes fees deferred during the year pursuant to a deferred compensation plan with Calamos Investment Trust. Deferred amounts are treated as though such amounts have been invested and reinvested in shares of one or more of the Calamos Funds selected by the trustee. As of December 31, 2004, the value of each of Messrs. Marsh's and Neal's deferred compensation account was $31,955 and $162,664, respectively.

* The Calamos Fund Complex consists of 14 portfolios, including the Fund.

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Prior to October 1, 2004, the compensation paid to the non-interested Trustees of the Calamos Funds for their services as such consisted of an annual retainer fee in the amount of $15,000. In addition, prior to September 27, 2004, the non-interested Trustees received a meeting attendance fee of $4,000 for any board meeting attended in person and $2,000 for any board meeting attended by telephone. The non-interested Trustees received $1,000 for any committee meeting attended (even if by telephone) and $4,000 for any special board meeting attended (even if by telephone).
Beginning on October 1, 2004, the compensation paid to the non-interested Trustees of Calamos Funds for their services as such consists of an annual retainer fee in the amount of $30,000. In addition, the chair of any committee receives an additional $5,000 annually. Non-interested Trustees receive a meeting attendance fee of $6,000 for any board meeting attended in person and $3,000 for any board meeting attended by telephone. In addition, non-interested Trustees receive $2,000 for any committee meeting attended (even if by telephone) and $3,000 for any special board meeting attended (even if by telephone). Beginning on April 1, 2005, the lead Independent Trustee receives an annual retainer of $60,000.
Compensation is paid only to Trustees who are not interested persons of Calamos or CAM and is allocated among the portfolios of the Calamos Funds in accordance with a procedure determined from time to time by the Board.

The Fund has adopted a deferred compensation plan (the "Plan"). Under the Plan, a Trustee who is not an "interested person" of Calamos and who has elected to participate in the Plan ("participating Trustees") may defer receipt of all or a portion of his compensation from the Fund in order to defer payment of income taxes or for other reasons. The deferred compensation payable to the participating Trustee is credited to the Trustee's deferral account as of the business day such compensation would have been paid to the Trustee. The value of a Trustee's deferred compensation account at any time is equal to what would be the value if the amounts credited to the account had instead been invested in shares of one or more of the portfolios of Calamos Investment Trust as designated by the Trustee. Thus, the value of the account increases with contributions to the account or with increases in the value of the measuring shares, and the value of the account decreases with withdrawals from the account or with declines in the value of the measuring shares. If a participating trustee retires, the Trustee may elect to receive payments under the Plan in a lump sum or in equal installments over a period of five years. If a participating Trustee dies, any amount payable under the Plan will be paid to the Trustee's beneficiaries.

OWNERSHIP OF SHARES OF THE FUND AND OTHER CALAMOS FUNDS. The following table indicates the value of shares that each Trustee beneficially owns in the Fund and the Calamos Fund Complex in the aggregate. The value of shares of the Calamos Funds is determined on the basis of the net asset value of the class of shares held as of December 31, 2004. The value of the shares held are stated in ranges in accordance with the requirements of the Commission. The table reflects the Trustee's beneficial ownership of shares of the Calamos Fund Complex. Beneficial ownership is determined in accordance with the rules of the Commission.

                                                     DOLLAR RANGE OF            AGGREGATE DOLLAR RANGE OF EQUITY
                                                  EQUITY SECURITIES IN       SECURITIES IN ALL REGISTERED INVESTMENT
              NAME OF TRUSTEE                           THE FUND                 COMPANIES IN THE CALAMOS FUNDS
---------------------------------------------     --------------------       ---------------------------------------
INTERESTED TRUSTEES:
John P. Calamos..............................             None                           over $100,000
Nick P. Calamos..............................             None                           over $100,000
Weston W. Marsh..............................             None                           over $100,000

NON-INTERESTED TRUSTEES:
Joe F. Hanauer...............................             None                           over $100,000
John E. Neal.................................             None                           over $100,000
William Rybak................................             None                           over $100,000
Stephen B. Timbers...........................             None                           over $100,000

CODE OF ETHICS. The Fund and Calamos have adopted a code of ethics under Rule 17j-1 of the 1940 Act that is applicable to officers, directors/Trustees and designated employees of Calamos and CFS. Employees of Calamos and CFS are permitted to make personal securities transactions, including transactions in securities that the Fund may purchase, sell or hold, subject to requirements and restrictions set forth in the code of ethics of Calamos and CFS. The code of ethics contains provisions and requirements designed to identify and address certain conflicts of interest between personal investment activities of Calamos and CFS employees and the interests of investment advisory clients such as the Fund. Among other things, the code of ethics prohibits certain types of transactions absent prior approval, imposes time periods during which personal transactions may not be made in certain securities, and requires the submission of duplicate broker confirmations and statements and quarterly reporting of securities transactions. Additional restrictions apply to portfolio managers, traders, research analysts and others involved in the investment advisory process. Exceptions to these and other provisions of the code of ethics may be granted in particular circumstances after review by appropriate personnel. Text-only versions of the code of ethics can be viewed online or downloaded from the EDGAR Database on the Commission's internet web site at www.sec.gov. You may review and copy the code of ethics by visiting the Commission's Public Reference Room in Washington, D.C. Information on the operation of the

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Public Reference Room may be obtained by calling the Commission at 202-551-8090. In addition, copies of the code of ethics may be obtained, after mailing the appropriate duplicating fee, by writing to the Commission's Public Reference Section, 100 F Street, N.E., Washington, DC 20549 or by e-mail request at publicinfo@sec.gov.

PROXY VOTING PROCEDURES. The Fund has delegated proxy voting responsibilities to Calamos, subject to the Board of Trustees' general oversight. The Fund expects Calamos to vote proxies related to the Fund's portfolio securities for which the Fund has voting authority consistent with the Fund's best economic interests. Calamos has adopted its own Proxy Voting Policies and Procedures ("Policies"). The Policies address, among other things, conflicts of interest that may arise between the interests of the Fund, and the interests of the adviser and its affiliates.

The following is a summary of the Policies used by Calamos in voting proxies.

To assist it in voting proxies, Calamos has established a Committee comprised of members of its Portfolio Management and Research Departments. The Committee and/or its members will vote proxies using the following guidelines.

In general, if Calamos believes that a company's management and board have interests sufficiently aligned with the Fund's interest, Calamos will vote in favor of proposals recommended by a company's board. More specifically, Calamos seeks to ensure that the board of directors of a company is sufficiently aligned with security holders' interests and provides proper oversight of the company's management. In many cases this may be best accomplished by having a majority of independent board members. Although Calamos will examine board member elections on a case-by-case basis, it will generally vote for the election of directors that would result in a board comprised of a majority of independent directors.

Because of the enormous variety and complexity of transactions that are presented to shareholders, such as mergers, acquisitions, reincorporations, adoptions of anti-take over measures (including adoption of a shareholder rights plan, requiring supermajority voting on particular issues, adoption of fair price provisions, issuance of blank check preferred stocks and the creation of a separate class of stock with unequal voting rights), changes to capital structures (including authorizing additional shares, repurchasing stock or approving a stock split), executive compensation and option plans, that occur in a variety of industries, companies and market cycles, it is extremely difficult to foresee exactly what would be in the best interests of the Fund in all circumstances. Moreover, voting on such proposals involves considerations unique to each transaction. Accordingly, Calamos will vote on a case-by-case basis on proposals presenting these transactions.

Finally, Calamos has established procedures to help resolve conflicts of interests that might arise when voting proxies for the Fund. These procedures provide that the Committee, along with Calamos' Legal and Compliance Departments, will examine conflicts of interests with the Fund of which Calamos is aware and seek to resolve such conflicts in the best interests of the Fund, irrespective of any such conflict. If a member of the Committee has a personal conflict of interest, that member will refrain from voting and the remainder of the Committee will determine how to vote the proxy solely on the investment merits of any proposal. The Committee will then memorialize the conflict and the procedures used to address the conflict.

The Fund is required to file with the SEC its complete proxy voting record for the twelve-month period ending June 30, by no later than August 31 of each year. The Fund's proxy voting record for the most recent twelve-month period ending June 30 is available by August 31 of each year (1) on the SEC's website at www.sec.gov and (2) without charge, upon request, by calling 800-582-6959.

You may obtain a copy a Calamos' Policies by calling (800) 582-6959, by visiting the Fund's website at www.calamos.com, by writing Calamos at: Calamos Investments, Attn: Client Services, 2020 Calamos Court, Naperville, IL 60563, and on the Commission's website at www.sec.gov.

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INVESTMENT ADVISER AND INVESTMENT MANAGEMENT AGREEMENT. Subject to the overall authority of the board of trustees, Calamos provides the Fund with investment research, advice and supervision and furnishes continuously an investment program for the Fund. In addition, Calamos furnishes for use of the Fund such office space and facilities as the Fund may require for its reasonable needs and supervises the business and affairs of the Fund and provides the following other services on behalf of the Fund and not provided by persons not a party to the investment management agreement: (i) preparing or assisting in the preparation of reports to and meeting materials for the Trustees; (ii) supervising, negotiating contractual arrangements with, to the extent appropriate, and monitoring the performance of, accounting agents, custodians, depositories, transfer agents and pricing agents, accountants, attorneys, printers, underwriters, brokers and dealers, insurers and other persons in any capacity deemed to be necessary or desirable to Fund operations; (iii) assisting in the preparation and making of filings with the Commission and other regulatory and self-regulatory organizations, including, but not limited to, preliminary and definitive proxy materials, amendments to the Fund's registration statement on Form N-2 and semi-annual reports on Form N-SAR and Form N-CSR; (iv) overseeing the tabulation of proxies by the Fund's transfer agent; (v) assisting in the preparation and filing of the Fund's federal, state and local tax returns; (vi) assisting in the preparation and filing of the Fund's federal excise tax return pursuant to Section 4982 of the Code; (vii) providing assistance with investor and public relations matters; (viii) monitoring the valuation of portfolio securities and the calculation of net asset value; (ix) monitoring the registration of shares of beneficial interest of the Fund under applicable federal and state securities laws; (x) maintaining or causing to be maintained for the Fund all books, records and reports and any other information required under the 1940 Act, to the extent that such books, records and reports and other information are not maintained by the Fund's custodian or other agents of the Fund; (xi) assisting in establishing the accounting policies of the Fund; (xii) assisting in the resolution of accounting issues that may arise with respect to the Fund's operations and consulting with the Fund's independent accountants, legal counsel and the Fund's other agents as necessary in connection therewith; (xiii) reviewing the Fund's bills; (xiv) assisting the Fund in determining the amount of dividends and distributions available to be paid by the Fund to its shareholders, preparing and arranging for the printing of dividend notices to shareholders, and providing the transfer and dividend paying agent, the custodian, and the accounting agent with such information as is required for such parties to effect the payment of dividends and distributions; and (xv) otherwise assisting the Fund as it may reasonably request in the conduct of the Fund's business, subject to the direction and control of the Trustees.

Under the investment management agreement, the Fund pays to Calamos a fee based on the average weekly managed assets that is computed weekly and paid on a monthly basis. The fee paid by the Fund is at the annual rate of 1.00% of managed assets. Because the fees paid to Calamos are determined on the basis of the Fund's managed assets, Calamos' interest in determining whether to leverage the Fund may differ from the interests of the Fund.

Under the terms of its investment management agreement with the Fund, except for the services and facilities provided by Calamos as set forth therein, the Fund shall assume and pay all expenses for all other Fund operations and activities and shall reimburse Calamos for any such expenses incurred by Calamos. The expenses borne by the Fund shall include, without limitation: (a) organization expenses of the Fund (including out-of-pocket expenses, but not including the Manager's overhead or employee costs); (b) fees payable to Calamos; (c) legal expenses; (d) auditing and accounting expenses; (e) maintenance of books and records that are required to be maintained by the Fund's custodian or other agents of the Fund; (f) telephone, telex, facsimile, postage and other communications expenses; (g) taxes and governmental fees; (h) fees, dues and expenses incurred by the Fund in connection with membership in investment company trade organizations and the expense of attendance at professional meetings of such organizations; (i) fees and expenses of accounting agents, custodians, subcustodians, transfer agents, dividend disbursing agents and registrars; (j) payment for portfolio pricing or valuation services to pricing agents, accountants, bankers and other specialists, if any; (k) expenses of preparing share certificates;

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(l) expenses in connection with the issuance, offering, distribution, sale, redemption or repurchase of securities issued by the Fund; (m) expenses relating to investor and public relations provided by parties other than Calamos; (n) expenses and fees of registering or qualifying shares of beneficial interest of the Fund for sale; (o) interest charges, bond premiums and other insurance expenses; (p) freight, insurance and other charges in connection with the shipment of the Fund's portfolio securities; (q) the compensation and all expenses (specifically including travel expenses relating to Fund business) of Trustees, officers and employees of the Fund who are not affiliated persons of Calamos; (r) brokerage commissions or other costs of acquiring or disposing of any portfolio securities of the Fund; (s) expenses of printing and distributing reports, notices and dividends to shareholders; (t) expenses of preparing and setting in type, printing and mailing prospectuses and statements of additional information of the Fund and supplements thereto; (u) costs of stationery; (v) any litigation expenses; (w) indemnification of Trustees and officers of the Fund; (x) costs of shareholders' and other meetings; (y) interest on borrowed money, if any; and (z) the fees and other expenses of listing the Fund's shares on the New York Stock Exchange or any other national stock exchange.

Unless earlier terminated as described below, the investment management agreement will remain in effect until August 1, 2006. The investment management agreement continues in effect from year to year so long as such continuation is approved at least annually by (1) the board of trustees or the vote of a majority of the outstanding voting securities (as defined in the 1940 Act) of the Fund, and (2) a majority of the Trustees who are not interested persons of any party to the investment management agreement, cast in person at a meeting called for the purpose of voting on such approval. The investment management agreement may be terminated at any time, without penalty, by either the Fund or Calamos upon 60 days' written notice, and is automatically terminated in the event of its assignment as defined in the 1940 Act.

Calamos is an indirect subsidiary of Calamos Asset Management, Inc., whose voting shares are majority-owned by Calamos Family Partners, Inc., which is controlled by John P. Calamos, Sr. and the Calamos family.

FACTORS CONSIDERED BY THE INDEPENDENT TRUSTEES IN APPROVING THE INVESTMENT MANAGEMENT AGREEMENT. The Fund's investment management agreement is required to be approved before it is entered into, and may be continued annually beyond its initial term both by the Board of Trustees and by a majority of the Independent Trustees voting separately. The Independent Trustees have determined that the terms of the Fund's investment management agreement are fair and reasonable and that the agreement is in the Fund's best interests. The Independent Trustees believe that the investment management agreement will enable the Fund to obtain high quality investment management services at a cost that they deem appropriate, reasonable and in the best interests of the Fund and its shareholers. In making such determinations, the Independent Trustees relied upon the assistance of counsel to the Independent Trustees.

In evaluating the investment management agreement, the Independent Trustees reviewed materials furnished by Calamos, including information regarding Calamos, its affiliates, their personnel, operations and financial condition, and the factors set out in judicial decisions and SEC directives relating to the approval of advisory contracts, which include but are not limited to the following: (a) the nature and quality of Calamos' services; (b) Calamos' investment performance; (c) Calamos' cost in providing its services;
(d) the extent to which Calamos realizes economies of scale as the Fund grows larger; and (e) the extent to which Calamos realizes other benefits from its role as the Fund's adviser.

Nature and Quality of Services. The Trustees reviewed the nature, extent and quality of services Calamos is expected to provide to the Fund, taking into account the Fund's investment objective and strategy and the Trustees' knowledge gained from their regular meetings with management on at least a quarterly basis. At a meeting held in June 2005, the Trustees reviewed narrative and statistical information concerning the types of services that Calamos currently provides to other funds it advises, Calamos' performance record with other funds it advises, and the performance of comparable, unaffiliated funds. In addition, the Trustees reviewed Calamos' resources and key personnel, especially those who provide investment management services to the Fund. The Trustees also considered other services to be provided to the Fund by Calamos, such as managing the execution of portfolio transactions and the selection of broker-dealers for those transactions, monitoring adherence to the Fund's investment restrictions, producing shareholder reports, providing support services for the Board and Board committees, communicating with shareholders and overseeing the activities of other service providers, including monitoring compliance with various Fund policies and procedures and with applicable securities laws and regulations.

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At a meeting held in October 2005, the Trustees concluded that the nature and extent of the services to be provided by Calamos to the Fund are appropriate and consistent with the terms of the investment management agreement and that the Fund is likely to benefit from the continued provision of those services. They also concluded that Calamos had sufficient personnel, with the appropriate education and experience, to serve the Fund effectively and had demonstrated its continuing ability to attract and retain well qualified personnel.

Fees, Expenses and Profitability. In evaluating the management fees and expenses that the Fund is expected to bear, the Trustees considered the Fund's management fee, the Fund's expected expense ratios and the fees and expenses of comparable funds. The Trustees also considered the ratio of Calamos' fees to their costs and the amount of its profit in relation to the nature and quality of services rendered to other Calamos funds, institutional separate accounts and other subadvised funds to determine whether its compensation is fair and reasonable. At their June 2005 meeting, the Trustees also looked at Calamos' expense allocation methodology. In evaluating the reasonableness of Calamos' compensation, the Trustees considered the following information provided at the June 2005 meeting, among other things: (a) the methodology used by Calamos in determining compensation payable to portfolio managers; (b) the very competitive environment for investment management talent; (c) the competitive market for mutual funds in different distribution channels; and (d) Calamos' financial condition, which they found to be sound.

The Trustees concluded that the management fees and other compensation payable by the Fund to Calamos is reasonable in relation to the nature and quality of the services to be provided, taking into account the fees charged by other advisers for managing comparable mutual funds with similar strategies and the fees Calamos charges to other clients. The Trustees also concluded that the Fund's estimated overall expense ratios, taking into account quality of services provided by Calamos and the investment performance of the other Calamos funds, were also reasonable.

Economies of Scale. The Trustees noted that the advisory fee schedule for the Fund does not contain breakpoints that reduce the fee rate on assets above specified levels. The Trustees received and discussed information concerning whether Calamos realizes economies of scale as the assets under its management increase. The Trustees concluded that the fee schedule for the Fund currently in effect represents an appropriate sharing of economies of scale at current asset levels but concluded to continue their periodic consideration of economies of scale.

Other Benefits to Calamos. The Trustees also considered benefits that accrue to Calamos and its affiliates from their relationship with the Fund. The Trustees concluded that, other than the services to be provided by Calamos pursuant to the investment management agreement and the fees payable by the Fund therefor, the Fund and Calamos may potentially benefit from their relationship with each other in other ways. The Trustees also considered Calamos' use of commissions to be paid by the Fund on its portfolio brokerage transactions to obtain proprietary research products and services benefiting the Fund and/or other Calamos clients. The Trustees concluded that Calamos' expected use of "soft" commission dollars to obtain research products and services is consistent with regulatory requirements and is expected to be beneficial to the Fund. They concluded that, although Calamos may derive additional benefits through the use of soft dollars from the Fund's portfolio transactions, the Fund also benefits from the receipt of research products and services to be acquired through commissions paid on the portfolio transactions of other Calamos clients. They also concluded that the Fund's success could attract other business to Calamos or its other funds and that Calamos' success could enhance its ability to serve the Fund.

The Trustees did not identify any single factor as all-important or controlling. After full consideration of the above factors as well as other factors that were instructive in analyzing the management arrangements, the Trustees, including all of the Independent Trustees, concluded that the terms of the investment management agreement was fair and reasonable, that Calamos' fees are reasonable in light of the services to be provided to the Fund and that the Calamos investment management agreement should be approved.

The use of the name "Calamos" in the name of the Fund is pursuant to licenses granted by Calamos, and the Fund has agreed to change the names to remove those references if Calamos ceases to act as investment adviser to the Fund.
PORTFOLIO MANAGERS

John P. Calamos, Nick P. Calamos and John P. Calamos, Jr. share responsibility for managing the Fund's portfolio. The portfolio managers are supported by and lead a team of investment professionals whose valuable contributions create a synergy of expertise that can be applied across many different investment strategies.

The portfolio managers also have responsibility for the day-to-day management of accounts other than the Fund. Information regarding these other accounts is set forth below.

                              Number of Other Accounts Managed and Assets by Account Type as of August 31, 2005
                              ---------------------------------------------------------------------------------
                               Registered                     Other Pooled
                               Investment                      Investment                           Other
Portfolio Manager              Companies                        Vehicles                           Accounts
-----------------      --------------------------      ---------------------------        --------------------------
                        Accounts          Assets        Accounts           Assets          Accounts          Assets
John P. Calamos            18      30,326,587,028          3          143,837,394           25,550    10,587,994,407

Nick P. Calamos            18      30,326,587,028          3          143,837,394           25,550    10,587,994,407

John P. Calamos, Jr.        7      17,169,452,669          2           86,516,052           25,550    10,587,994,407

            Number of Accounts and Assets for which Advisory Fee is Performance Based as of August 31, 2005
            -----------------------------------------------------------------------------------------------
                               Registered                     Other Pooled
                               Investment                      Investment                           Other
Portfolio Manager              Companies                        Vehicles                           Accounts
-----------------      --------------------------      ---------------------------        --------------------------
                        Accounts          Assets        Accounts           Assets          Accounts           Assets
John P. Calamos             1          101,324,118         2           86,516,052            1             8,083,771

Nick P. Calamos             1          101,324,118         2           86,516,052            1             8,083,771

John P. Calamos, Jr.      None          None               2           86,516,052            1             8,083,771

The Fund's portfolio managers are responsible for managing the Fund and other accounts, including separate accounts and unregistered funds.

Other than potential conflicts between investment strategies, the side-by-side management of both the Fund and other accounts may raise potential conflicts of interest due to the interest held by Calamos in an account and certain trading practices used by the portfolio managers (e.g., cross trades between the Fund and another account and allocation of aggregated trades). Calamos has developed policies and procedures reasonably designed to mitigate those conflicts. For example, Calamos will only place cross-trades in securities held by the Fund in accordance with the rules promulgated under the 1940 Act and has adopted policies designed to ensure the fair allocation of securities purchased on an aggregated basis.

The portfolio managers advise certain accounts under a performance fee arrangement. A performance fee arrangement may create an incentive for a portfolio manager to make investments that are riskier or more speculative than would be the case in the absence of performance fees. A performance fee arrangement may result in increased compensation to the portfolio managers from such accounts due to unrealized appreciation as well as realized gains in the client's account.

As of December 31, 2004, the portfolio managers receive all of their compensation from Calamos Asset Management, Inc. The portfolio managers have each entered into employment agreements that provide for compensation in the form of a minimum annual base salary and a maximum discretionary target bonus. The amounts paid to portfolio managers and the criteria utilized to determine the amounts are benchmarked against industry specific data provided by third party analytical agencies. The discretionary target bonus is set at a percentage of base salary, ranging from 300% to 600% of base salary, with a maximum annual bonus opportunity of at least 150% of the target bonus. Portfolio performance, as measured by risk-adjusted portfolio performance, is utilized to determine the discretionary target bonus. Also, due to the portfolio managers' ownership and executive management positions with Calamos and its parent companies, additional multiple corporate objectives are utilized to determine the discretionary target bonus. For 2004, the additional corporate objectives were advisory fee revenue, measured by growth in revenues compared to industry percentages; marketing effectiveness, as measured by growth in assets under management relative to industry percentages; operating efficiencies, as measured by operating margin relative to industry levels; and stock price performance.

The portfolio managers are also eligible to receive annual equity awards under a long term incentive compensation program. The target annual equity awards are set at a percentage of base salary, ranging from 225% to 300%.

Prior to entering into employment agreements, John P. Calamos and Nick P. Calamos each received compensation in the form of salary, bonus and distributions due to their unique ownership positions with Calamos, its parent company and their predecessor companies. At that time, compensation for each portfolio manager was benchmarked against industry compensation standards for portfolio managers in comparable executive positions, with advisors managing comparably sized portfolios. Further, bonus and distributions were benchmarked against industry compensation standards, but also were determined by income growth, revenue growth and growth of assets under management.

At September 22, 2005, each portfolio manager beneficially owned (as determined pursuant to Rule 16a-1(a)(2) under the 1934 Act) shares of the Fund having values within the indicated dollar ranges.

                              FUND
                             -----
John P. Calamos               $0
Nick P. Calamos               $0
John P. Calamos, Jr.          $0

FUND ACCOUNTANT. Under the arrangements with State Street Bank and Trust Company ("State Street") to provide fund accounting services, State Street provides certain administrative and accounting services including providing daily reconciliation of cash, trades and positions; maintaining general ledger and capital stock accounts; preparing daily trial balance; calculating net asset value; providing selected general ledger reports; preferred share compliance; calculating total returns; and providing monthly distribution analysis to the Fund and such other funds advised by Calamos that may be part of those arrangements (the Fund and such other funds are collectively referred to as the "Calamos Funds"). For the services rendered to the Calamos Funds, State Street receives fees based on the combined managed assets of the Calamos Funds ("Combined Assets"). State Street receives a fee at the annual rate of .0175% for the first $1.5 billion of Combined Assets, .0150% for the next $1.5 billion of Combined Assets, .0125% for the next $1.5 billion in Combined Assets, .010% for the next $1.5 billion of Combined Assets, .0075% for the next $1.5 billion of Combined Assets and .00375% for the Combined Assets in excess of $7.5 billion. Each fund of the Calamos Funds pays its pro-rata share of the fees payable to State Street described below based on relative managed assets of each fund.

Calamos will provide the following financial accounting services to Calamos Funds, rather than State Street: management of expenses and expense payment processing; monitor the calculation of expense accrual amounts for any fund and make any necessary modifications; coordinate any expense reimbursement calculations and payment; calculate yields on the funds in accordance with rules and regulations of the Commission; calculate net investment income dividends and capital gains distributions; calculate track and report tax adjustments on all assets of each fund, including but not limited to contingent debt and preferred trust obligations; prepare excise tax and fiscal year distributions schedules; prepare tax information required for financial statement footnotes; prepare state and federal income tax returns; prepare specialized calculations of amortization on convertible securities; prepare year-end dividend disclosure information; calculate trustee deferred compensation plan accruals and valuations; and prepare Form 1099 information statements for Board members and service providers. For providing those financial accounting services, will receive a fee payable monthly at the annual rate of 0.0175% on the first $1 billion of Combined Assets; 0.0150% on the next $1 billion of Combined Assets; and 0.0110% on Combined Assets above $2 billion ("financial accounting service fee"). Each fund of the Calamos Funds will pay its pro-rata share of the financial accounting service fee payable to Calamos based on relative managed assets of each fund.

PORTFOLIO TRANSACTIONS

Portfolio transactions on behalf of the Fund effected on stock exchanges involve the payment of negotiated brokerage commissions. There is generally no stated commission in the case of securities

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traded in the over-the-counter markets, but the price paid by the Fund usually includes an undisclosed dealer commission or mark-up. In underwritten offerings, the price paid by the Fund includes a disclosed, fixed commission or discount retained by the underwriter or dealer.

In executing portfolio transactions, Calamos uses its best efforts to obtain for the Fund the most favorable combination of price and execution available. In seeking the most favorable combination of price and execution, Calamos considers all factors it deems relevant, including price, the size of the transaction, the nature of the market for the security, the amount of commission, the timing of the transaction taking into account market prices and trends, the execution capability of the broker-dealer and the quality of service rendered by the broker-dealer in other transactions.

In allocating the Fund's portfolio brokerage transactions to unaffiliated broker-dealers, Calamos may take into consideration the research, analytical, statistical and other information and services provided by the broker-dealer, such as general economic reports and information, reports or analyses of particular companies or industry groups, market timing and technical information, and the availability of the brokerage firm's analysts for consultation. Although Calamos believes these services have substantial value, they are considered supplemental to Calamos' own efforts in the performance of its duties under the management agreement. As permitted by Section 28(e) of the Securities Exchange Act of 1934 ("1934 Act"), Calamos may pay a broker-dealer that provides brokerage and research services an amount of commission for effecting a securities transaction for the Fund in excess of the commission that another broker-dealer would have charged for effecting that transaction if the amount is believed by Calamos to be reasonable in relation to the value of the overall quality of the brokerage and research services provided. Other clients of Calamos may indirectly benefit from the provision of these services to Calamos, and the Fund may indirectly benefit from services provided to Calamos as a result of transactions for other clients.

In certain cases, Calamos may obtain products or services from a broker that have both research and non-research uses. Examples of non-research uses are administrative and marketing functions. These are referred to as "mixed use" products. In each case, Calamos makes a good faith effort to determine the proportion of such products or services that may be used for research and non-research purposes. That determination is based upon the time spent by Calamos personnel for research and non-research uses. The portion of the costs of such products or services attributable to research usage may be defrayed by Calamos through brokerage commissions generated by transactions of its clients, including the Fund. Calamos pays the provider in cash for the non-research portion of its use of these products or services.

REPURCHASE OF COMMON SHARES

The Fund is a closed-end investment company and as such its shareholders will not have the right to cause the Fund to redeem their shares. Instead, the Fund's common shares will trade in the open market at a price that will be a function of several factors, including dividend levels (which are in turn affected by expenses), net asset value, call protection, dividend stability, relative demand for and supply of such shares in the market, general market and economic conditions and other factors. Because shares of a closed-end investment company may frequently trade at prices lower than net asset value, the Fund's Board of Trustees may consider action that might be taken to reduce or eliminate any material discount from net asset value in respect of common shares, which may include the repurchase of such shares in the open market or in private transactions, the making of a tender offer for such shares, or the conversion of the Fund to an open-end investment company. The Board of Trustees may decide not to take any of these

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actions. In addition, there can be no assurance that share repurchases or tender offers, if undertaken, will reduce market discount.

Notwithstanding the foregoing, at any time when the Fund's preferred shares are outstanding, the Fund may not purchase, redeem or otherwise acquire any of its common shares unless (1) all accumulated preferred shares dividends have been paid and (2) at the time of such purchase, redemption or acquisition, the net asset value of the Fund's portfolio (determined after deducting the acquisition price of the common shares) is at least 200% of the liquidation value of the outstanding preferred shares (expected to equal the original purchase price per share plus any accrued and unpaid dividends thereon). Any service fees incurred in connection with any tender offer made by the Fund will be borne by the Fund and will not reduce the stated consideration to be paid to tendering shareholders.

Subject to its investment restrictions, the Fund may borrow to finance the repurchase of shares or to make a tender offer. Interest on any borrowings to finance share repurchase transactions or the accumulation of cash by the Fund in anticipation of share repurchases or tenders will reduce the Fund's net income. Any share repurchase, tender offer or borrowing that might be approved by the Fund's Board of Trustees would have to comply with the Exchange Act, the 1940 Act and the rules and regulations thereunder.

Although the decision to take action in response to a discount from net asset value will be made by the Board of Trustees at the time it considers such issue, it is not currently anticipated that the Board of Trustees would authorize repurchases of common shares or a tender offer for such shares if: (1) such transactions, if consummated, would (a) result in the delisting of the common shares from the New York Stock Exchange, or (b) impair the Fund's status as a regulated investment company under the Code (which would make the Fund a taxable entity, causing the Fund's income to be taxed at the corporate level in addition to the taxation of shareholders who receive dividends from the Fund) or as a registered closed-end investment company under the 1940 Act; (2) the Fund would not be able to liquidate portfolio securities in an orderly manner and consistent with the Fund's investment objective and policies in order to repurchase shares; or (3) there is, in the board's judgment, any (a) material legal action or proceeding instituted or threatened challenging such transactions or otherwise materially adversely affecting the Fund, (b) general suspension of or limitation on prices for trading securities on the New York Stock Exchange, (c) declaration of a banking moratorium by federal or state authorities or any suspension of payment by United States or New York banks, (d) material limitation affecting the Fund or the issuers of its portfolio securities by federal or state authorities on the extension of credit by lending institutions or on the exchange of foreign currency, (e) commencement of war, armed hostilities or other international or national calamity directly or indirectly involving the United States, or (f) other event or condition that would have a material adverse effect (including any adverse tax effect) on the Fund or its shareholders if shares were repurchased.

The repurchase by the Fund of its shares at prices below net asset value will result in an increase in the net asset value of those shares that remain outstanding. However, there can be no assurance that share repurchases or tender offers at or below net asset value will result in the Fund's shares trading at a price equal to their net asset value. Nevertheless, the fact that the Fund's shares may be the subject of repurchase or tender offers from time to time, or that the Fund may be converted to an open-end investment company, may reduce any spread between market price and net asset value that might otherwise exist.

In addition, a purchase by the Fund of its common shares will decrease the Fund's total managed assets, which would likely have the effect of increasing the Fund's expense ratio. Any purchase by the Fund of its common shares at a time when preferred shares are outstanding will increase the leverage applicable to the outstanding common shares then remaining. Before deciding whether to take any action

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if the common shares trade below net asset value, the Fund's Board of Trustees would likely consider all relevant factors, including the extent and duration of the discount, the liquidity of the Fund's portfolio, the impact of any action that might be taken on the Fund or its shareholders and market considerations. Based on these considerations, even if the Fund's shares should trade at a discount, the Board of Trustees may determine that, in the interest of the Fund and its shareholders, no action should be taken.

U.S. FEDERAL INCOME TAX MATTERS

The following is a summary discussion of certain U.S. federal income tax consequences that may be relevant to a shareholder that acquires, holds and/or disposes of common shares of the Fund. This discussion only addresses U.S. federal income tax consequences to U.S. shareholders who hold their shares as capital assets and does not address all of the U.S. federal income tax consequences that may be relevant to particular shareholders in light of their individual circumstances. This discussion also does not address the tax consequences to shareholders who are subject to special rules, including, without limitation, banks and financial institutions, insurance companies, dealers in securities or foreign currencies, foreign holders, persons who hold their shares as or in a hedge against currency risk, a constructive sale, or conversion transaction, holders who are subject to the alternative minimum tax, or tax-exempt or tax-deferred plans, accounts, or entities. In addition, the discussion does not address any state, local, or foreign tax consequences. The discussion reflects applicable tax laws of the United States as of the date hereof, which tax laws may be changed or subject to new interpretations by the courts or the Internal Revenue Service ("IRS") retroactively or prospectively and could affect the continued validity of this summary. No attempt is made to present a detailed explanation of all U.S. federal income tax concerns affecting the Fund and its shareholders, and the discussion set forth herein does not constitute tax advice. INVESTORS ARE URGED TO CONSULT THEIR OWN TAX ADVISERS BEFORE MAKING AN INVESTMENT IN THE FUND TO DETERMINE THE SPECIFIC TAX CONSEQUENCES TO THEM OF INVESTING IN THE FUND, INCLUDING THE APPLICABLE FEDERAL, STATE, LOCAL AND FOREIGN TAX CONSEQUENCES AS WELL AS THE EFFECT OF POSSIBLE CHANGES IN TAX LAWS.

The Fund intends to elect to be treated and to qualify each year as a "regulated investment company" under Subchapter M of the Internal Revenue Code of 1986, as amended (the "Code") so that it will not pay U.S. federal income tax on income and capital gains timely distributed to shareholders. In order to qualify as a regulated investment company under Subchapter M of the Code, the Fund must, among other things, derive at least 90% of its gross income for each taxable year from dividends, interest, payments with respect to securities loans, gains from the sale or other disposition of stock, securities or foreign currencies, or other income (including gains from options, futures and forward contracts) derived with respect to its business of investing in such stock, securities or currencies and net income derived from an interest in a qualified publicly traded partnership (collectively, the "90% income test"). For purposes of the 90% income test, the character of income earned by certain entities in which the Fund invests that are not treated as corporations (e.g., partnerships) for U.S. federal income tax purposes will generally pass through to the Fund. Consequently, the Fund may be required to limit its equity investments in such entities that earn fee income, rental income or other nonqualifying income. In addition to the 90% income test, the Fund must also diversify its holdings (commonly referred to as the "asset test") so that, at the end of each quarter of its taxable year (i) at least 50% of the value of the Fund's total assets is represented by cash and cash items, U.S. government securities, securities of other regulated investment companies and other securities, with such other securities of any one issuer limited for the purposes of this calculation to an amount not greater in value than 5% of the value of the Fund's total assets and to not more than 10% of the outstanding voting securities of such issuer, and
(ii) not more than 25% of the value of its total assets is invested in the securities of any one issuer (other than U.S. government securities or securities of other regulated investment companies) or of two or more issuers controlled by the Fund and engaged in the same, similar or related trades or businesses or the securities of one or more qualified publicly traded partnerships.

If the Fund qualifies as a regulated investment company and distributes to its shareholders at least 90% of the sum of (i) its "investment company taxable income" as that term is defined in the Code (which

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includes, among other things, dividends, taxable interest, and the excess of any net short-term capital gains over net long-term capital losses as reduced by certain deductible expenses) without regard to the deduction for dividends paid and (ii) the excess of its gross tax-exempt interest, if any, over certain disallowed deductions, the Fund will be relieved of U.S. federal income tax on any income of the Fund, including long-term capital gains, distributed to shareholders. However, if the Fund retains any investment company taxable income or "net capital gain" (i.e., the excess of net long-term capital gains over net short-term capital losses), it will be subject to U.S. federal income tax at regular corporate rates (currently at a maximum rate of 35%) on the amount retained. The Fund intends to distribute at least annually, all or substantially all of its investment company taxable income, net tax-exempt interest, and net capital gain. Under the Code, the Fund will be subject to a nondeductible 4% federal excise tax on a portion of its undistributed ordinary income and capital gains for any calendar year if it fails to meet certain distribution requirements with respect to such calendar year. The Fund intends to make distributions in a timely manner and accordingly does not expect to be subject to this excise tax.

If for any taxable year the Fund does not qualify as a regulated investment company for U.S. federal income tax purposes, it would be treated as a U.S. corporation subject to U.S. federal income tax and distributions to its shareholders would not be deductible by the Fund in computing its taxable income. In such event, the Fund's distributions, to the extent derived from the Fund's current or accumulated earnings and profits, would generally constitute ordinary dividends, which would be eligible for the dividends received deduction available to corporate shareholders under Section 243 of the Code, and non- corporate shareholders of the Fund generally would be able to treat such distributions as "qualified dividend income" under Section 1(h)(11) of the Code as discussed below.

Unless a shareholder is ineligible to participate or elects otherwise, all distributions will be automatically reinvested in additional common shares of the Fund pursuant to the Automatic Dividend Reinvestment Plan (the "Plan"). For U.S. federal income tax purposes, all dividends are generally taxable regardless of whether a shareholder takes them in cash or they are reinvested pursuant to the Plan in additional shares of the Fund. Distributions of investment company taxable income, which includes net investment income, net short-term capital gain in excess of net long-term capital loss and certain net foreign exchange gains, are generally taxable as ordinary income to the extent of the Fund's current and accumulated earnings and profits. Under Section 1(h)(11) of the Code, for taxable years beginning on or before December 31, 2008, qualified dividend income received by non-corporate shareholders is taxed at rates equivalent to long-term capital gain tax rates, which reach a maximum of 15%. "Qualified dividend income" generally includes dividends from certain domestic corporations and dividends from "qualified foreign corporations", although dividends paid by REITs will not generally be eligible to qualify as qualified dividend income. For these purposes, a "qualified foreign corporation" is a foreign corporation (i) that is incorporated in a possession of the United States or is eligible for benefits under a qualifying income tax treaty with the United States, or (ii) whose stock with respect to which such dividend is paid is readily tradable on an established securities market in the United States. A qualified foreign corporation does not include a foreign corporation that for the taxable year of the corporation in which the dividend was paid, or the preceding taxable year, is a "passive foreign investment company," as defined in the Code. The Fund generally can pass the tax treatment of qualified dividend income it receives through to Fund shareholders to the extent of the aggregate dividends received by the Fund. For the Fund to receive qualified dividend income, the Fund must meet certain holding period requirements for the stock on which the otherwise qualified

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dividend is paid. In addition, the Fund cannot be obligated to make payments (pursuant to a short sale or otherwise) with respect to substantially similar or related property. If the Fund lends portfolio securities, amounts received by the Fund that is the equivalent of the dividends paid by the issuer on the securities loaned will not be eligible for qualified dividend income treatment. The same provisions, including the holding period requirements, apply to each shareholder's investment in the Fund. After December 31, 2008, "qualified dividend income" will no longer be taxed at the rates applicable to long-term capital gains, but rather will be taxed at ordinary income tax rates, which can reach a maximum rate of 35%, unless Congress enacts legislation providing otherwise. Distributions of net capital gain, if any, are taxable at long-term capital gain rates for U.S. federal income tax purposes without regard to the length of time the shareholder has held shares of the Fund. A distribution of an amount in excess of the Fund's current and accumulated earnings and profits, if any, will be treated by a shareholder as a tax-free return of capital, which is applied against and reduces the shareholder's basis in his, her or its shares. To the extent that the amount of any such distribution exceeds the shareholder's basis in his, her or its shares, the excess will be treated by the shareholder as gain from the sale or exchange of such shares. The U.S. federal income tax status of all distributions will be designated by the Fund and reported to the shareholders annually.

Certain distributions by the Fund may qualify for the dividends received deduction available to corporate shareholders under Section 243 of the Code, subject to certain holding period and other requirements, but generally only to the extent the Fund earned dividend income from stock investments in U.S. domestic corporations (other than REITs).

If a shareholder's distributions are automatically reinvested pursuant to the Plan and the Plan Agent invests the distribution in shares acquired on behalf of the shareholder in open-market purchases, for U.S. federal income tax purposes, the shareholder will be treated as having received a taxable distribution in the amount of the cash dividend that the shareholder would have received if the shareholder had elected to receive cash. If a shareholder's distributions are automatically reinvested pursuant to the Plan and the Plan Agent invests the distribution in newly issued shares of the Fund, the shareholder will be treated as receiving a taxable distribution equal to the fair market value of the stock the shareholder receives.

If the Fund retains any net capital gain, the Fund may designate the retained amount as undistributed capital gains in a notice to shareholders who, if subject to U.S. federal income tax on long-term capital gains, (i) will be required to include in income, as long-term capital gain, their proportionate share of such undistributed amount, and (ii) will be entitled to credit their proportionate share of the tax paid by the Fund on the undistributed amount against their U.S. federal income tax liabilities, if any, and to claim refunds to the extent the credit exceeds such liabilities. For U.S. federal income tax purposes, the tax basis of shares owned by a shareholder of the Fund will be increased by the difference between the amount of undistributed net capital gain included in the shareholder's gross income and the tax deemed paid by the shareholders.

Any dividend declared by the Fund in October, November or December with a record date in such a month and paid during the following January will be treated for U.S. federal income tax purposes as paid by the Fund and received by shareholders on December 31 of the calendar year in which it is declared.

Foreign exchange gains and losses realized by the Fund in connection with certain transactions involving foreign currency-denominated debt securities, certain options and futures contracts relating to foreign currency, foreign currency forward contracts, foreign currencies, or payables or receivables denominated in a foreign currency are subject to Section 988 of the Code, which generally causes such gain and loss to be treated as ordinary income or loss and may affect the amount, timing and character of distributions to shareholders.

If the Fund acquires any equity interest (generally including not only stock but also an option to acquire stock such as is inherent in a convertible bond) in certain foreign corporations that receive at least 75% of their annual gross income from passive sources (such as interest, dividends, certain rents and royalties, or capital gains) or that hold at least 50% of their assets in investments producing such passive

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income ("passive foreign investment companies"), the Fund could be subject to U.S. federal income tax and additional interest charges on "excess distributions" received from such companies or on gain from the sale of stock in such companies, even if all income or gain actually received by the Fund is timely distributed to its shareholders. The Fund would not be able to pass through to its shareholders any credit or deduction for such a tax. An election may generally be available that would ameliorate these adverse tax consequences, but any such election could require the Fund to recognize taxable income or gain (subject to tax distribution requirements) without the concurrent receipt of cash and would also require the foreign corporation to provide the Fund with certain information necessary for such treatment, which such foreign corporation may or may not provide. These investments could also result in the treatment of associated capital gains as ordinary income. The Fund may limit and/or manage its holdings in passive foreign investment companies to limit its tax liability or maximize its return from these investments.

If more than 50% of the value of a Fund's total assets at the close of any taxable year consists of stock or securities in foreign corporations, and such Fund distributes at least 90% of its investment company taxable income and net tax exempt interest, the Fund may file an election with the IRS pursuant to which shareholders of the Fund will be required to (i) include in gross income (in addition to taxable dividends actually received) their pro rata shares of foreign income taxes paid by the Fund even though not actually received, (ii) treat such respective pro rata shares as foreign income taxes paid by them, and
(iii) deduct such pro rata shares in computing their U.S. federal taxable income, or, alternatively, use them as foreign tax credits, subject to applicable limitations, against their U.S. federal income tax liability. Shareholders who do not itemize deductions for federal income tax purposes will not, however, be able to deduct their pro rata portion of foreign taxes paid by such Fund, although such shareholders will be required to include their share of such taxes in gross income. Shareholders who claim a foreign tax credit may be required to treat a portion of dividends received from the Fund as separate category income for purposes of computing the limitations on the foreign tax credit available to such shareholders. Tax-exempt shareholders will not ordinarily benefit from this election relating to foreign taxes. Each year, the Funds will notify their respective shareholders of the amount of (i) each shareholder's pro rata share of foreign income taxes paid by such Fund and (ii) the portion of such Fund's dividends that represents income from each foreign country, if the Fund qualifies to pass along such credit. If a Fund does not make such an election, the net investment income of the Fund will be reduced by, and its shareholders will not be able to deduct their pro rata share of, foreign taxes paid by the Fund.

The Fund may invest in debt obligations that are in the lowest rating categories or are unrated, including debt obligations of issuers not currently paying interest or who are in default. Investments in debt obligations that are at risk of or in default present special tax issues for the Fund. Tax rules are not entirely clear about issues such as when the Fund may cease to accrue interest, original issue discount or market discount, when and to what extent deductions may be taken for bad debts or worthless securities and how payments received on obligations in default should be allocated between principal and income. These and other related issues will be addressed by the Fund when, as and if it invests in such securities, in order to seek to ensure that it distributes sufficient income to preserve its status as a regulated investment company and does not become subject to U.S. federal income or excise taxes.

If the Fund utilizes leverage through borrowing, asset coverage limitations imposed by the 1940 Act as well as additional restrictions that may be imposed by certain lenders on the payment of dividends or distributions could potentially limit or eliminate the Fund's ability to make distributions on its common shares until the asset coverage is restored. These limitations could prevent the Fund from distributing at least 90% of its investment company taxable income as is required under the Code and therefore might jeopardize the Fund's qualification as a regulated investment company and/or might subject the Fund to a nondeductible 4% federal excise tax. Upon any failure to meet the asset coverage requirements imposed by the 1940 Act, the Fund may, in its sole discretion and to the extent permitted under the 1940 Act, purchase or redeem shares of preferred stock in order to maintain or restore the requisite asset coverage and avoid the adverse consequences to the Fund and its shareholders of failing to meet the distribution requirements. There can be no assurance, however, that any such action would achieve these objectives. The Fund will endeavor to avoid restrictions on its ability to distribute dividends.

If the Fund invests in certain pay-in-kind securities, zero coupon securities, deferred interest securities or, in general, any other securities with original issue discount (or with market discount if the Fund elects to include market discount in income currently), the Fund must accrue income on such investments for each taxable year, which generally will be prior to the receipt of the corresponding cash payments. However, the Fund must distribute, at least annually, all or substantially all of its net investment income, including such accrued income, to shareholders to avoid U.S. federal income and excise taxes. Therefore, the Fund may have to dispose of its portfolio securities under disadvantageous circumstances to generate cash, or may have to leverage itself by borrowing the cash, to satisfy distribution requirements.

At the time of an investor's purchase of the Fund's shares, a portion of the purchase price may be attributable to realized or unrealized appreciation in the Fund's portfolio or undistributed taxable income of the Fund. Consequently, subsequent distributions by the Fund with respect to these shares from such appreciation or income may be taxable to such investor even if the net asset value of the investor's shares is, as a result of the distributions, reduced below the investor's cost for such shares and the distributions

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economically represent a return of a portion of the investment. Sales and other dispositions of the Fund's shares generally are taxable events for shareholders that are subject to federal income tax. Shareholders should consult their own tax advisors regarding their individual circumstances to determine whether any particular transaction in the Fund's shares is properly treated as a sale or exchange for tax purposes (as the following discussion assumes) and the tax treatment of any gains or losses recognized in such transactions. Generally, gain or loss will be equal to the difference between the amount of cash and the fair market value of other property realized and the shareholder's adjusted tax basis in the shares sold or exchanged. In general, any gain or loss realized upon a taxable disposition of shares will be treated as long-term capital gain or loss if the shares have been held for more than one year. Otherwise, the gain or loss on the taxable disposition of the Fund's shares will be treated as short-term capital gain or loss. However, any loss realized by a shareholder upon the sale or other disposition of shares with a tax holding period of six months or less will be treated as a long-term capital loss to the extent of any amounts treated as distributions of long-term capital gain with respect to such shares. Long-term capital gain rates applicable to noncorporate shareholders have been reduced--in general, to 15% with lower rates applying to taxpayers in the 10% and 15% rate brackets--for taxable years beginning on or before December 31, 2008. After December 31, 2008, the maximum noncorporate tax rate on long term capital gains will increase to 20%, unless Congress enacts legislation providing otherwise. The availability to deduct capital losses may be subject to limitations. In addition, losses on sales or other dispositions of shares may be disallowed under the "wash sale" rules in the event a shareholder acquires substantially identical shares (including those made pursuant to reinvestment of dividends) within a period of 61 days beginning 30 days before and ending 30 days after a sale or other disposition of shares. In such a case, the disallowed portion of any loss generally would be included in the U.S. federal tax basis of the shares acquired.

From time to time the Fund may repurchase its shares. Shareholders who tender all shares held, or considered to be held (through attribution), by them will be treated as having sold their shares and generally will realize a capital gain or loss. If a shareholder tenders fewer than all of its shares, such shareholder may be treated as having received a taxable dividend upon the tender of its shares. In such a case, there is a remote risk that non-tendering shareholders will be treated as having received taxable distributions from the Fund. To the extent that the Fund recognizes net gains on the liquidation of portfolio securities to meet such tenders of shares, the Fund will be required to make additional distributions to its shareholders.

The Fund may engage in various transactions utilizing options, futures contracts, forward contracts, hedge instruments, straddles, and other similar transactions. Such transactions may be subject to special provisions of the Code that, among other things, affect the character of any income realized by the Fund from such investments, accelerate recognition of income to the Fund, defer Fund losses, and affect the determination of whether capital gain or loss is characterized as long-term or short-term capital gain or loss. These rules could therefore affect the character, amount and timing of distributions to shareholders. These provisions may also require the Fund to mark-to-market certain types of the positions in its portfolio (i.e., treat them as if they were closed out), which may cause the Fund to recognize income without receiving cash with which to make distributions in amounts necessary to satisfy the distribution requirements for avoiding U.S. federal income and excise taxes. The Fund will monitor its transactions, will make the appropriate tax elections, and will make the appropriate entries in its books and records when it acquires an option, futures contract, forward contract, hedge instrument or other similar investment in order to mitigate the effect of these rules, prevent disqualification of the Fund as a regulated investment company and minimize the imposition of U.S. federal income and excise taxes.

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The IRS has taken the position that if a regulated investment company has two classes of shares, it must designate distributions made to each class in any year as consisting of no more than such class's proportionate share of particular types of income (e.g., dividends qualifying for the dividends received deduction, "qualified dividend income," ordinary income and net capital gains). Consequently, if both common shares and preferred shares are outstanding, the Fund intends to designate distributions made to each class of particular types of income in accordance with each class' proportionate shares of such income. Thus, the Fund will designate dividends qualifying for the corporate dividends received deduction, "qualified dividend income," ordinary income and net capital gain in a manner that allocates such income between the holders of common shares and preferred shares in proportion to the total dividends made to each class during or for the taxable year, or otherwise as required by applicable law. However, for purposes of determining whether distributions are out of the Fund's current or accumulated earnings and profits, the Fund's earnings and profits will be allocated first to the Fund's preferred shares, if any, and then to the Fund's common shares. In such a case, since the Fund's current and accumulated earnings and profits will first be used to pay dividends on the preferred shares, distributions in excess of such earnings and profits, if any, will be made disproportionately to holders of common shares.

The Fund may invest in REITs that hold residual interests in real estate mortgage investment conduits ("REMICs"). Under Treasury regulations that have not yet been issued, but may apply retroactively, a portion of the Fund's income from a REIT that is attributable to the REIT's residual interest in a REMIC (referred to in the Code as an "excess inclusion") will be subject to federal income tax in all events. These regulations are also expected to provide that excess inclusion income of a regulated investment company, such as the Fund, will be allocated to shareholders of the regulated investment company in proportion to the dividends received by such shareholders, with the same consequences as if the shareholders held the related REMIC residual interest directly. In general, excess inclusion income allocated to shareholders (i) cannot be offset by net operating losses (subject to a limited exception for certain thrift institutions), (ii) will constitute unrelated business taxable income to entities (including a qualified pension plan, an individual retirement account, a 401(k) plan, a Keogh plan or other tax-exempt entity) subject to tax on unrelated business income, thereby potentially requiring such an entity that is allocated excess inclusion income, and otherwise might not be required to file a tax return, to file a tax return and pay tax on such income, and (iii) in the case of a foreign shareholder, will not qualify for any reduction in U.S. federal withholding tax. In addition, if at any time during any taxable year a "disqualified organization" (as defined in the Code) is a record holder of a share in a regulated investment company, then the regulated investment company will be subject to a tax equal to that portion of its excess inclusion income for the taxable year that is allocable to the disqualified organization, multiplied by the highest federal income tax rate imposed on corporations. The Fund does not intend to invest in REITs in which a substantial portion of the assets will consist of residual interests in REMICs.

The Fund may be subject to withholding and other taxes imposed by foreign countries, including taxes on interest, dividends and capital gains with respect to its investments in those countries, which would, if imposed, reduce the yield on or return from those investments. Tax treaties between certain countries and the U.S. may reduce or eliminate such taxes in some cases. As explained above, the Fund may be able to make an election to pass through to its shareholders their pro rata share of qualified foreign taxes paid by the Fund. However, if the Fund can not make this election, shareholders will not be able to include such taxes in their gross incomes and will not be entitled to a tax deduction or credit for such taxes on their own federal income tax returns.

Federal law requires that the Fund withhold, as "backup withholding," 28% of reportable payments, including dividends, capital gain distributions and the proceeds of sales or other dispositions of the Fund's shares paid to shareholders who have not complied with IRS regulations. In order to avoid this withholding requirement, shareholders must certify on their Account Applications, or on a separate IRS Form W-9, that the Social Security Number or other Taxpayer Identification Number they provide is their correct number and that they are not currently subject to backup withholding, or that they are exempt

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from backup withholding. The Fund may nevertheless be required to withhold if it receives notice from the IRS or a broker that the number provided is incorrect or backup withholding is applicable as a result of previous underreporting of interest or dividend income. Backup withholding is not an additional tax. Any amount withheld may be allowed as a refund or a credit against the shareholder's U.S. federal income tax liability if the appropriate information (such as the filing the appropriate federal income tax return) is provided to the IRS.

Under Treasury regulations, if a shareholder recognizes a loss with respect to shares of $2 million or more in a single taxable year (or $4 million or more in any combination of taxable years) for an individual shareholder, S corporation or trust or $10 million or more in a single taxable year (or $20 million or more in any combination of years) for a shareholder who is a C corporation, such shareholder will generally be required to file with the IRS a disclosure statement on Form 8886. Direct shareholders of portfolio securities are generally excepted from this reporting requirement, but under current guidance, shareholders of a regulated investment company are not excepted. Future guidance may extend the current exception from this reporting requirement to shareholders of most or all regulated investment companies. The fact that a loss is reportable under these regulations does not affect the legal determination of whether the taxpayer's treatment of the loss is proper. Shareholders should consult their tax advisors to determine the applicability of these regulations in light of their individual circumstances.

The description of certain U.S. federal income tax provisions above relates only to U.S. federal income tax consequences for shareholders who are U.S. persons (i.e., U.S. citizens or residents or U.S. corporations, partnerships, trusts or estates). Investors other than U.S. persons may be subject to different U.S. tax treatment, including a non-resident alien U.S. withholding tax at the rate of 30% or at a lower treaty rate on amounts treated as ordinary dividends from the Fund provided a valid and effective IRS Form W-8BEN is on file with the Fund. SHAREHOLDERS SHOULD CONSULT THEIR OWN TAX
ADVISORS ON THESE MATTERS AND ON ANY SPECIFIC QUESTION OF U.S. FEDERAL, STATE, LOCAL, FOREIGN AND OTHER APPLICABLE TAX LAWS BEFORE MAKING AN INVESTMENT IN THE FUND.

EXPERTS

The financial statements of the Fund as of October 17, 2005 appearing in this statement of additional information have been audited by Deloitte & Touche LLP, 2 Prudential Plaza, 180 N. Stetson, Chicago, Illinois, 60601, independent auditors, as set forth in their report thereon appearing elsewhere herein, and is included in reliance upon such report given upon the authority of such firm as experts in accounting and auditing.

ADDITIONAL INFORMATION

A Registration Statement on Form N-2, including amendments thereto, relating to the shares offered hereby, has been filed by the Fund with the Commission, Washington, D.C. The prospectus and this statement of additional information do not contain all of the information set forth in the Registration Statement, including any exhibits and schedules thereto. For further information with respect to the Fund and the shares offered hereby, reference is made to the Registration Statement. Statements contained in the prospectus and this statement of additional information as to the contents of any contract or other document referred to are not necessarily complete and in each instance reference is made to the copy of such contract or other document filed as an exhibit to the Registration Statement, each such statement being qualified in all respects by such reference. A copy of the Registration Statement may be inspected without charge at the Commission's principal office in Washington, D.C., and copies of all or any part thereof may be obtained from the Commission upon the payment of certain fees prescribed by the Commission.

S-40

Financial Statements and Report of Independent Registered Public Accounting Firm


REPORT OF INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM

To the Board of Trustees and Shareholders of Calamos Global Total Return Fund:

We have audited the accompanying statement of assets and liabilities of Calamos Global Total Return Fund (the "Fund") as of October 17, 2005, and the related statements of operations for the period from March 30, 2004 (date of organization) through October 31, 2004 and for the period from November 1, 2004 through October 17, 2005. These financial statements are the responsibility of the Fund's management. Our responsibility is to express an opinion on these financial statements based on our audit.

We conducted our audit in accordance with the standards of the Public Company Accounting Oversight Board (United States). Those standards require that we plan and perform the audit to obtain reasonable assurance about whether the financial statements are free of material misstatement. The Fund is not required to have, nor were we engaged to perform, an audit of its internal control over financial reporting. Our audit included consideration of internal control over financial reporting as a basis for designing audit procedures that are appropriate in the circumstances, but not for the purpose of expressing an opinion on the effectiveness of the Fund's internal control over financial reporting. Accordingly, we express no such opinion. An audit also includes examining, on a test basis, evidence supporting the amounts and disclosures in the financial statements, assessing the accounting principles used and significant estimates made by management, as well as evaluating the overall financial statement presentation. We believe that our audit provides a reasonable basis for our opinion.

In our opinion, the financial statements referred to above present fairly, in all material respects, the financial position of Calamos Global Total Return Fund as of October 17, 2005 and the results of its operations for the period from March 30, 2004 (date of organization) through October 31, 2004 and for the period from November 1, 2004 through October 17, 2005, in conformity with accounting principles generally accepted in the United States of America.

/S/  Deloitte & Touche LLP

Chicago, Illinois
October 25, 2005

F-1

CALAMOS GLOBAL TOTAL RETURN FUND
STATEMENT OF ASSETS AND LIABILITIES
OCTOBER 17, 2005

ASSETS:
Cash ..............................................................   $100,000

Deferred offering costs ...........................................    150,000
                                                                      --------
Total assets ......................................................    250,000
                                                                      --------
LIABILITIES:
Accrued offering costs ............................................    150,000
                                                                      --------
Net assets (6,980.80 shares of beneficial interest issued
          and outstanding; unlimited shares authorized) ...........   $100,000
                                                                      --------
Net asset value per share .........................................   $ 14.325
                                                                      --------

STATEMENT OF OPERATIONS
FOR THE PERIOD FROM MARCH 30, 2004 (DATE OF ORGANIZATION)
THROUGH OCTOBER 31, 2004

Investment income ..............................   $    -
                                                   ------
Organizational expenses ........................        -
Less: reimbursement from investment advisor ....        -
                                                   ------
Net expenses ...................................        -
                                                   ------
Net investment income ..........................   $    -
                                                   ------

STATEMENT OF OPERATIONS
FOR THE PERIOD FROM NOVEMBER 1, 2004 THROUGH OCTOBER 17, 2005

Investment income...............................   $    -
                                                   ------
Organizational expenses.........................        -
Less: reimbursement from investment advisor.....        -
                                                   ------
Net expenses....................................        -
                                                   ------
Net investment income...........................   $    -
                                                   ------

NOTES

1. ORGANIZATION

Calamos Global Total Return Fund (the "Fund") is a diversified, closed-end management investment company, organized on March 30, 2004 which has had no operations other than the sale and issuance of 6,981 shares of beneficial interest at an aggregate purchase price of $100,000 to Calamos Advisors LLC (the "Investment Adviser" or "Calamos"). The Fund estimates that it will offer $75,000,000 in common shares in its initial offering. The Investment Adviser has agreed to pay the amount by which the aggregate of all of the Fund's organizational expenses and all offering costs (other than the sales load) exceeds $0.03 per share. Accordingly, the Fund's share of offering costs will be recorded as a reduction of the proceeds from the sale of its Common Shares upon the commencement of the Fund's operations. Estimated offering costs to be borne by the Fund total $150,000. All of the estimated organizational costs of $85,384 are being paid by Calamos. The Fund currently anticipates that it will issue Preferred Shares as soon as practicable after the closing of the initial offering of common shares.

F-2

2. ACCOUNTING POLICIES

The preparation of the financial statements in accordance with accounting principles generally accepted in the United States of America requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities at the date of the financial statements and the reported amounts of income and expenses during the reporting period. Actual results could differ from these estimates.

3. AGREEMENTS

The Fund has entered into an Investment Advisory Agreement with Calamos, which provides for payment of a monthly fee computed at the annual rate of 1.00% of the Fund's average weekly Managed Assets. "Managed Assets" means the total assets of the Fund (including any assets attributable to leverage) minus accrued liabilities (other than liabilities representing leverage). For purposes of calculating "Managed Assets," the liquidation preference of any Preferred Shares outstanding is not considered a liability.

The Fund and other closed end funds advised by Calamos that are part of these arrangements (the Fund and such other funds are collectively referred to as the "Calamos Closed End Funds") have entered into a Fund Accounting Servicing Agreement with State Street Bank & Trust Co. ("State Street"). The Calamos Closed End Funds will pay State Street a monthly fee based on combined Managed Assets of the Calamos Closed End Funds ("Combined Assets") at the annual rate of 0.0175% for the first $1.5 billion of Combined Assets; 0.0150% on the next $1.5 billion of Combined Assets; 0.0125% on the next $1.5 billion of Combined Assets; 0.0100% on the next $1.5 billion of Combined Assets; 0.0075% on the next $1.5 billion of Combined Assets; and 0.00375% for the Combined Assets that exceed $7.5 billion. Each fund of the Calamos Closed End Funds will pay its pro-rata share of the fees payable to State Street based on relative Managed Assets of each fund.

The Fund and other funds advised by Calamos that are part of these arrangements (the Fund and such other funds are collectively referred to as the "Calamos Funds") have also entered into a Financial Accounting Servicing Agreement with Calamos. The Calamos Funds will pay Calamos a monthly fee based on combined Managed Assets of the Calamos Funds ("Complex Assets") at the annual rate of 0.0175% on the first $1 billion of Complex Assets; 0.0150% on the next $1 billion of Complex Assets; and 0.0110% on Complex Assets that exceed $2 billion. Each fund of the Calamos Funds will pay its pro-rata share of the fees payable to Calamos based on relative Managed Assets of each fund.

4. FEDERAL INCOME TAXES

The Fund intends to qualify as a "regulated investment company" and as such (and by complying with the applicable provisions of the Internal Revenue Code of 1986, as amended) will not be subject to Federal income tax on taxable income (including realized capital gains) that is distributed to shareholders.

F-3

APPENDIX A--DESCRIPTION OF RATINGS(1)

MOODY'S PRIME RATING SYSTEM

Moody's short-term ratings are opinions of the ability of issuers to honor senior financial obligations and contracts. Such obligations generally have an original maturity not exceeding one year, unless explicitly noted.

Moody's employs the following designations, all judged to be investment grade, to indicate the relative repayment ability of rated issuers:

Prime-1: Issuers rated Prime-1 (or supporting institutions) have a superior ability for repayment of senior short-term debt obligations. Prime-1 repayment ability will often be evidenced by many of the following characteristics:

- Leading market positions in well-established industries.

- High rates of return on funds employed.

- Conservative capitalization structure with moderate reliance on debt and ample asset protection.

- Broad margins in earnings coverage of fixed financial charges and high internal cash generation.

- Well-established access to a range of financial markets and assured sources of alternate liquidity.

Prime-2: Issuers (or supporting institutions) rated Prime-2 have a strong ability to repay senior short-term debt obligations. This will normally be evidenced by many of the characteristics cited above, but to a lesser degree. Earnings trends and coverage ratios, while sound, may be more subject to variation. Capitalization characteristics, while still appropriate, may be more affected by external conditions. Ample alternate liquidity is maintained.

Prime-3: Issuers (or supporting institutions) rated Prime-3 have an acceptable ability for repayment of senior short-term obligations. The effect of industry characteristics and market compositions may be more pronounced. Variability in earnings and profitability may result in changes in the level of debt-protection measurements and may require relatively high financial leverage. Adequate alternate liquidity is maintained.

Not Prime: Issuers rated Not Prime do not fall within any of the Prime rating categories.

In addition, in certain countries the prime rating may be modified by the issuer's or guarantor's senior unsecured long-term debt rating.

MOODY'S DEBT RATINGS

Aaa: Bonds and preferred stock that are rated Aaa are judged to be of the best quality. They carry the smallest degree of investment risk and are generally referred to as "gilt edged." Interest payments are protected by a large or by an exceptionally stable margin and principal is secure. While the various protective elements are likely to change, such changes as can be visualized are most unlikely to impair the fundamentally strong position of such issues.


(1) The ratings indicated herein are believed to be the most recent ratings available at the date of this prospectus for the securities listed. Ratings are generally given to securities at the time of issuance. While the rating agencies may from time to time revise such ratings, they undertake no obligation to do so, and the ratings indicated do not necessarily represent ratings that will be given to these securities on the date of the fund's fiscal year-end.

A-1

Aa: Bonds and preferred stock that are rated Aa are judged to be of high quality by all standards. Together with the Aaa group they comprise what are generally known as high-grade bonds. They are rated lower than the best bonds because margins of protection may not be as large as in Aaa securities or fluctuation of protective elements may be of greater amplitude or there may be other elements present that make the long-term risk appear somewhat larger than the Aaa securities.

A: Bonds and preferred stock that are rated A possess many favorable investment attributes and are to be considered as upper-medium-grade obligations. Factors giving security to principal and interest are considered adequate, but elements may be present that suggest a susceptibility to impairment some time in the future.

Baa: Bonds and preferred stock that are rated Baa are considered as medium-grade obligations (i.e., they are neither highly protected nor poorly secured). Interest payments and principal security appear adequate for the present but certain protective elements may be lacking or may be characteristically unreliable over any great length of time. Such bonds lack outstanding investment characteristics and in fact have speculative characteristics as well.

Ba: Bonds and preferred stock that are rated Ba are judged to have speculative elements; their future cannot be considered as well-assured. Often the protection of interest and principal payments may be very moderate, and thereby not well safeguarded during both good and bad times over the future. Uncertainty of position characterizes bonds in this class.

B: Bonds and preferred stock that are rated B generally lack characteristics of the desirable investment. Assurance of interest and principal payments or of maintenance of other terms of the contract over any long period of time may be small.

Caa: Bonds and preferred stock that are rated Caa are of poor standing. Such issues may be in default or there may be present elements of danger with respect to principal or interest.

Ca: Bonds and preferred stock that are rated Ca represent obligations which are speculative in a high degree. Such issues are often in default or have other marked shortcomings.

C: Bonds and preferred stock that are rated C are the lowest rated class of bonds, and issues so rated can be regarded as having extremely poor prospects of ever attaining any real investment standing.

Moody's assigns ratings to individual debt securities issued from medium-term note (MTN) programs, in addition to indicating ratings to MTN programs themselves. Notes issued under MTN programs with such indicated ratings are rated at issuance at the rating applicable to all pari passu notes issued under the same program, at the program's relevant indicated rating, provided such notes do not exhibit any of the characteristics listed below. For notes with any of the following characteristics, the rating of the individual note may differ from the indicated rating of the program:

1) Notes containing features that link interest or principal to the credit performance of any third party or parties.

2) Notes allowing for negative coupons, or negative principal.

3) Notes containing any provision that could obligate the investor to make any additional payments.

4) Notes containing provisions that subordinate the claim.

A-2

Market participants must determine whether any particular note is rated, and if so, at what rating level.

Note: Moody's applies numerical modifiers 1, 2, and 3 in each generic rating classification from Aa through Caa. The modifier 1 indicates that the obligation ranks in the higher end of its generic rating category; the modifier 2 indicates a mid-range ranking; and the modifier 3 indicates a ranking in the lower end of that generic rating category.

STANDARD & POOR'S SHORT-TERM ISSUE CREDIT RATINGS

A-1: A short-term obligation rated A-1 is rated in the highest category by Standard & Poor's. The obligor's capacity to meet its financial commitment on the obligation is strong. Within this category, certain obligations are designated with a plus sign (+). This indicates that the obligor's capacity to meet its financial commitment on these obligations is extremely strong.

A-2: A short-term obligation rated A-2 is somewhat more susceptible to the adverse effects of changes in circumstances and economic conditions than obligations in higher rating categories. However, the obligor's capacity to meet its financial commitment on the obligation is satisfactory.

A-3: A short-term obligation rated A-3 exhibits adequate protection parameters. However, adverse economic conditions or changing circumstances are more likely to lead to a weakened capacity of the obligor to meet its financial commitment on the obligation.

B: A short-term obligation rated B is regarded as having significant speculative characteristics. The obligor currently has the capacity to meet its financial commitment on the obligation; however, it faces major ongoing uncertainties, which could lead to the obligor's inadequate capacity to meet its financial commitment on the obligation.

C: A short-term obligation rated C is currently vulnerable to nonpayment and is dependent upon favorable business, financial, and economic conditions for the obligor to meet its financial commitment on the obligation.

D: A short-term obligation rated D is in payment default. The D rating category is used when payments on an obligation are not made on the date due even if the applicable grace period has not expired, unless Standard & Poor's believes that such payments will be made during such grace period. The D rating also will be used upon the filing of a bankruptcy petition or the taking of a similar action if payments on an obligation are jeopardized.

STANDARD & POOR'S LONG-TERM ISSUE CREDIT RATINGS

Issue credit ratings are based, in varying degrees, on the following considerations:

- Likelihood of payment-capacity and willingness of the obligor to meet its financial commitment on an obligation in accordance with the terms of the obligation;

- Nature of and provisions of the obligation;

- Protection afforded by, and relative position of, the obligation in the event of bankruptcy, reorganization, or other arrangement under the laws of bankruptcy and other laws affecting creditors' rights.

A-3

The issue rating definitions are expressed in terms of default risk. As such, they pertain to senior obligations of an entity. Junior obligations are typically rated lower than senior obligations, to reflect the lower priority in bankruptcy, as noted above. (Such differentiation applies when an entity has both senior and subordinated obligations, secured and unsecured obligations, or operating company and holding company obligations.) Accordingly, in the case of junior debt, the rating may not conform exactly with the category definition.

AAA: An obligation rated AAA has the highest rating assigned by Standard & Poor's. The obligor's capacity to meet its financial commitment on the obligation is extremely strong.

AA: An obligation rated AA differs from the highest rated obligations only in small degree. The obligor's capacity to meet its financial commitment on the obligation is very strong.

A: An obligation rated A is somewhat more susceptible to the adverse effects of changes in circumstances and economic conditions than obligations in higher rated categories. However, the obligor's capacity to meet its financial commitment on the obligation is still strong.

BBB: An obligation rated BBB exhibits adequate protection parameters. However, adverse economic conditions or changing circumstances are more likely to lead to a weakened capacity of the obligor to meet its financial commitment on the obligation.

Obligations rated BB, B, CCC, CC, and C are regarded as having significant speculative characteristics. BB indicates the least degree of speculation and C the highest. While such obligations will likely have some quality and protective characteristics, these may be outweighed by large uncertainties or major exposures to adverse conditions.

BB: An obligation rated BB is less vulnerable to nonpayment than other speculative issues. However, it faces major ongoing uncertainties or exposure to adverse business, financial, or economic conditions that could lead to the obligor's inadequate capacity to meet its financial commitment on the obligation.

B: An obligation rated B is more vulnerable to nonpayment than obligations rated BB, but the obligor currently has the capacity to meet its financial commitment on the obligation. Adverse business, financial, or economic conditions will likely impair the obligor's capacity or willingness to meet its financial commitment on the obligation.

CCC: An obligation rated CCC is currently vulnerable to nonpayment, and is dependent upon favorable business, financial, and economic conditions for the obligor to meet its financial commitment on the obligation. In the event of adverse business, financial, or economic conditions, the obligor is not likely to have the capacity to meet its financial commitment on the obligation.

CC: An obligation rated CC is currently highly vulnerable to nonpayment.

C: The C rating may be used to cover a situation where a bankruptcy petition has been filed or similar action taken, but payments on this obligation are being continued.

D: An obligation rated D is in payment default. The D rating category is used when payments on an obligation are not made on the date due even if the applicable grace period has not expired, unless Standard & Poor's believes that such payments will be made during such grace period. The D rating also

A-4

will be used upon the filing of a bankruptcy petition or the taking of a similar action if payments on an obligation are jeopardized.

Plus (+) or Minus (-): The ratings from AA to CCC may be modified by the addition of a plus or minus sign to show relative standing within the major rating categories.

R: This symbol is attached to the ratings of instruments with significant noncredit risks. It highlights risks to principal or volatility of expected returns that are not addressed in the credit rating.

N.R.: This indicates that no rating has been requested, that there is insufficient information on which to base a rating, or that Standard & Poor's does not rate a particular obligation as a matter of policy.

LOCAL CURRENCY AND FOREIGN CURRENCY RISKS

Country risk considerations are a standard part of Standard & Poor's analysis for credit ratings on any issuer or issue. Currency of repayment is a key factor in this analysis. An obligor's capacity to repay foreign currency obligations may be lower than its capacity to repay obligations in its local currency due to the sovereign government's own relatively lower capacity to repay external versus domestic debt. These sovereign risk considerations are incorporated in the debt ratings assigned to specific issues. Foreign currency issuer ratings are also distinguished from local currency issuer ratings to identify those instances where sovereign risks make them different for the same issuer.

A-5

PART C -- OTHER INFORMATION

ITEM 25: FINANCIAL STATEMENTS AND EXHIBITS

1. Financial Statements:

The Registrant's statement of assets and liabilities (balance sheet) dated October 17, 2005, notes to that financial statement and report of independent registered public accountants thereon are filed herewith in the Statement of Additional Information.

2. Exhibits:

                 a.1.       Agreement and Declaration of Trust. (*)
                 a.2.       Certificate of Trust. (*)
                 b.         By-laws. (*)
                 c.         None.
                 d.         Form of Share Certificate. (**)
                 e.         Terms and Conditions of the Dividend Reinvestment
                            Plan. (**)
                 f.         None.
                 g.         Investment Management Agreement with Calamos
                            Advisors LLC (**)
                 h.1.       Form of Underwriting Agreement. (**)
                 h.2.       Form of Standard Dealer Agreement. (**)
                 h.3.       Master Agreement Among Underwriters. (**)
                 i.         None.
                 j.1.       Form of Custody Agreement. (**)
                 j.2.       Form of Foreign Custody Manager Agreement. (**)
                 k.1        Form of Stock Transfer Agency Agreement. (**)
                 k.2        Master Services Agreement (***)
                 k.3        Financial Accounting Services Agreement (**)
                 l.1.       Opinion of Vedder, Price, Kaufman & Kammholz,
                            P.C. (**)
                 l.2.       Opinion of Morris, Nichols, Arsht & Tunnell. (**)
                 m.         None.
                 n.         Consent of Auditors. (***)
                 o.         Not applicable.
                 p.         Subscription Agreement. (***)
                 q.         None.
                 r.1.       Code of Ethics. (**)
                 s.         Powers of Attorney (*)


------------------

(*) Incorporated by reference to Registrant's Registration Statement as filed with the Commission via EDGAR on March 31, 2004.
(**) Incorporated by reference to Registrant's Registration Statement as filed with the Commission via EDGAR on October 24, 2005. (***) Filed herewith.

C-1

ITEM 26: MARKETING ARRANGEMENTS

Reference will be made to the underwriting agreement for the Registrant's shares of beneficial interest to be filed in an amendment to the Registrant's Registration Statement.

ITEM 27: OTHER EXPENSES OF ISSUANCE AND DISTRIBUTION

The following table sets forth the estimated expenses to be incurred in connection with the offering described in this Registration Statement:

Registration fees..................................   $   13,536
New York Stock Exchange listing fee................      150,000
Printing (other than certificates).................      250,000
Engraving and printing certificates................        1,500
Accounting fees and expenses.......................       15,000
Legal fees and expenses............................      200,000
NASD fee...........................................       30,000
Miscellaneous......................................       28,709
                                                      ----------
Total..............................................   $  688,745
                                                      ==========

ITEM 28. PERSONS CONTROLLED BY OR UNDER COMMON CONTROL

None.

ITEM 29. NUMBER OF HOLDERS OF SECURITIES

As of October 1, 2005, the number or record holders of each class of

securities of the Registrant was

               TITLE OF CLASS                   NUMBER OF RECORD HOLDERS
               --------------                   ------------------------
   Common Shares (no par value)..........                  --

ITEM 30. INDEMNIFICATION

The Registrant's Agreement and Declaration of Trust (the "Declaration"), dated March 12, 2004, provides that every person who is, or has been, a Trustee or an officer, employee or agent of the Registrant (including any individual who serves at its request as director, officer, partner, employee, Trustee, agent or the like of another organization in which it has any interest as a shareholder, creditor or otherwise) ("Covered Person") shall be indemnified by the Registrant or the appropriate series of the Registrant to the fullest extent permitted by law against liability and against all expenses reasonably incurred or paid by him in connection with any claim, action, suit or proceeding in which he becomes involved as a party or otherwise by virtue of his being or having been a Covered Person and against amounts paid or incurred by him in the settlement thereof; provided that no indemnification shall be provided to a Covered Person (i) who shall have been adjudicated by a court or body before which the proceeding was brought (A) to be liable to the Registrant or its shareholders by reason of willful misfeasance, bad faith, gross negligence or reckless disregard of the duties involved in the conduct of his office, or (B) not to have acted in good faith and in a manner the person reasonably believed to be or not opposed to the best interest of the Registrant; or (ii) in the event of a settlement, unless there has been a determination that such Covered Person did not engage in willful misfeasance, bad faith, gross negligence or reckless disregard of the duties involved in the conduct of his office; (A) by the court or other body

C-2

approving the settlement; (B) by at least a majority of those Trustees who are neither Interested Persons of the Registrant nor are parties to the matter based upon a review of readily available facts (as opposed to a full trial-type inquiry); (C) by written opinion of independent legal counsel based upon a review of readily available facts (as opposed to a full trial-type inquiry) or (D) by a vote of a majority of the Outstanding Shares entitled to vote (excluding any Outstanding Shares owned of record or beneficially by such individual).

The Declaration also provides that if any shareholder or former shareholder of any series of the Registrant shall be held personally liable solely by reason of his being or having been a shareholder and not because of his acts or omissions or for some other reason, the shareholder or former shareholder (or his heirs, executors, administrators or other legal representatives or in the case of any entity, its general successor) shall be entitled out of the assets belonging to the applicable series of the Registrant to be held harmless from and indemnified against all loss and expense arising from such liability. The Registrant, on behalf of its affected series, shall, upon request by such shareholder, assume the defense of any claim made against such shareholder for any act or obligation of the series and satisfy any judgment thereon from the assets of the series.

Insofar as indemnification for liability arising under the Securities Act of 1933, as amended (the "1933 Act"), may be available to Trustees, officers and controlling persons of the Registrant pursuant to the foregoing provisions, or otherwise, the Registrant has been advised that in the opinion of the Commission such indemnification is against public policy as expressed in the 1933 Act and is, therefore, unenforceable. In the event that a claim for indemnification against such liabilities (other than the payment by the Registrant's expenses incurred or paid by a Trustee, officer or controlling person of the Registrant in the successful defense of any action, suit or proceeding) is asserted by such Trustee, officer or controlling person in connection with the securities being registered, the Registrant will, unless in the opinion of its counsel the matter has been settled by controlling precedent, submit to a court of appropriate jurisdiction the question whether such indemnification by it is against public policy as expressed in the 1933 Act and will be governed by the final adjudication of such issue.

ITEM 31. BUSINESS AND OTHER CONNECTIONS OF INVESTMENT ADVISER

The information in the Statement of Additional Information under the caption "Management--Trustees and Officers" is incorporated by reference.

ITEM 32. LOCATION OF ACCOUNTS AND RECORDS

All such accounts, books, and other documents are maintained at the offices of the Registrant, at the offices of the Registrant's investment manager, Calamos Asset Management, Inc., 1111 East Warrenville Road, Naperville, Illinois 60563, at the offices of the custodian, 100 Church Street, New York, New York 10286 or at the offices of the transfer agent, 111 8th Avenue, New York, New York 10011-5201.

ITEM 33. MANAGEMENT SERVICES

Not applicable.

ITEM 34. UNDERTAKINGS

1. The Registrant undertakes to suspend the offering of shares until the prospectus is amended if (1) subsequent to the effective date of its registration statement, the net asset value declines more than ten percent from its net asset value as of the effective date of the registration statement or
(2) the net asset value increases to an amount greater than its net proceeds as stated in the prospectus.

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2. Not applicable.

3. Not applicable.

4. Not applicable.

5. (a) For the purposes of determining any liability under the 1933 Act, the information omitted from the form of prospectus filed as part of a registration statement in reliance upon Rule 430A and contained in the form of prospectus filed by the Registrant under Rule 497(h) under the 1933 Act shall be deemed to be part of the Registration Statement as of the time it was declared effective.

(b) For the purpose of determining any liability under the 1933 Act, each post-effective amendment that contains a form of prospectus shall be deemed to be a new registration statement relating to the securities offered therein, and the offering of the securities at that time shall be deemed to be the initial bona fide offering thereof.

6. The Registrant undertakes to send by first class mail or other means designed to ensure equally prompt delivery within two business days of receipt of a written or oral request the Registrant's statement of additional information.

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SIGNATURES

Pursuant to the requirements of the Securities Act of 1933 and/or Investment Company Act of 1940, the Registrant has duly caused this registration statement to be signed on its behalf by the undersigned, thereunto duly authorized, in this City of Naperville and State of Illinois, on the 25th day of October, 2005.

CALAMOS GLOBAL TOTAL RETURN FUND

By: /s/ John P. Calamos
    --------------------------------------
    John P. Calamos, Trustee and President

Pursuant to the requirements of the Securities Act of 1933, this registration statement has been signed by the following persons in the capacities and on the date(s) indicated.

/s/ John P. Calamos                 Trustee and President (Principal Executive      October 25, 2005
----------------------------------  Officer)
John P. Calamos

/s/ Patrick Dudasik                 Vice President (Principal Financial and         October 25, 2005
----------------------------------  Accounting Officer)
Patrick Dudasik

Nick P. Calamos*                    Trustee                                         By: /s/ James S. Hamman, Jr.
                                                                                        ------------------------
Joe E. Hanauer*                     Trustee                                             James S. Hamman, Jr.
                                                                                        Attorney-In-Fact
John E. Neal*                       Trustee                                             October 25, 2005

Weston W. Marsh*                    Trustee

William Rybak*                      Trustee

* Original powers of attorney authorizing James S. Hamman, Jr. and John P. Calamos to execute this Registration Statement, and Amendments thereto, for each of the trustees on whose behalf this Registration Statement is filed, have been executed and filed as exhibits to Registrant's Registration Statement as filed with the Commission via EDGAR on March 31, 2004.

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                 EXHIBIT INDEX

EXHIBIT                  DOCUMENT

 k.2        Master Services Agreement.
 n.         Consent of Auditors.
 p.         Subscription Agreement.


Exhibit K2

MASTER SERVICES AGREEMENT

This AGREEMENT is made as of March 15, 2004 by and among each registered management investment company identified on Appendix A hereto (each such management investment company and each management investment company made subject to this Agreement in accordance with Section 8.5 below shall hereinafter be referred to as a "FUND" and are sometimes collectively hereinafter referred to as the "FUNDS"), and STATE STREET BANK AND TRUST COMPANY, a Massachusetts trust company, having its principal place of business at 225 Franklin Street, Boston, Massachusetts 02110 (the "AGENT").

WHEREAS, each Fund desires to retain the Agent to perform certain services;

WHEREAS, each Fund may or may not be authorized to issue common stock or shares of beneficial interest ("SHARES") in separate series, with each such series representing interests in a separate portfolio of securities and other assets;

WHEREAS, each Fund so authorized intends that this Agreement be applicable to its series of Shares (as identified on Appendix A hereto (such series together with all other series subsequently established by such Fund and made subject to this Agreement in accordance with Section 8.6 below, shall hereinafter be referred to as the "PORTFOLIO(S)");

WHEREAS, each Fund not so authorized intends that this Agreement be applicable to it and that all references hereinafter to one or more "Portfolio(s)" shall be deemed to refer to such Fund(s); and

WHEREAS, the Agent is willing to perform such services upon the terms and conditions hereinafter set forth.

Now, THEREFORE, in consideration of the mutual covenants and agreements hereinafter contained, the parties hereto agree as follows:

SECTION 1. DUTIES OF THE AGENT.

SECTION 1.1 BOOKS OF ACCOUNT.

The Agent shall maintain the books of account of each Fund and shall perform the following duties in the manner prescribed by such Fund's currently effective prospectus, statement of additional information or other governing document, certified copies of which have been supplied to the Agent (a "GOVERNING DOCUMENT"):

a. Maintain each Portfolio's general ledger and such other accounts, books and financial records of such Portfolio as the parties may agree upon from time to time, and as may be required by the Investment Company Act of 1940, as amended (the "1940 ACT");


b. Maintain each Portfolio's portfolio security transaction records utilizing trade date provided to the Agent by such Portfolio's duly authorized investment adviser (each, an "INVESTMENT ADVISER");

c. For each valuation date, post each Portfolio's transactions to such Portfolio's general ledger including, but not limited to:

- Calculate unrealized appreciation and depreciation regarding portfolio securities;

- Amortize premiums and discounts regarding portfolio securities, as applicable;

- Calculate fee-based expenses and set-up expense accruals as directed by the applicable Fund;

- Record payments of Portfolio expenses upon written instructions of a Fund or duly authorized agent thereof;

- Calculate interest and dividend income and reset interest accrual for variable rate securities, as applicable

d. Reconcile cash, foreign currency and portfolio security holding positions with each Portfolio's custodian (each, a "CUSTODIAN") daily,

e. Post each Portfolio's corporate actions;

f. Calculate the net asset value of each Portfolio and report same to the Fund or such other entities or persons as the Fund may instruct from time to time;

g. Prepare and transmit to the Fund, or such other entities or persons as the Fund may instruct from time to time, such periodic reports of Fund data as may be mutually agreed upon by the parties hereto; and

h. Post shareholder reinvestment activity and reconcile share balances with each Portfolio's transfer agent (each, a "TRANSFER AGENT") in conjunction with Portfolio distributions.

Each Fund shall provide timely prior notice to the Agent of any modification in the manner in which such calculations are to be performed as prescribed in any revision to such Fund's governing document and shall supply the Agent with certified copies of all amendments and/or supplements to the governing documents in a timely manner. For purposes of calculating the net asset value of a Fund, the Agent shall value each Fund's portfolio securities utilizing prices obtained from sources designated by such Fund (collectively, the "AUTHORIZED PRICE SOURCES") on a Price Source Authorization substantially in the form attached hereto as Exhibit A, as the same may be amended from time to time, or otherwise designated by means of Proper Instructions (as such term is defined in Section 2.2 below) (the "PRICE SOURCE AUTHORIZATION"). The Agent shall not be responsible for any revisions to the methods of calculation unless and until such revisions are communicated in writing to the Agent.

2.


SECTION 1.2 ADDITIONAL SERVICES.

The Agent shall provide the following services, as applicable, in each case, subject to the control, supervision and direction of each Fund and subject to any necessary review and comments by the Fund's auditors and legal counsel and in accordance with procedures or policies that maybe established from time to time by and between the Agent and the Fund:

a. Prepare and distribute daily total return calculations;

b. Prepare monthly distribution analysis;

c. Complete monthly preferred shares "asset coverage" test (as that term is defined in Section 18(h) of the 1940 Act following agreed-upon compliance procedures (the "COMPLIANCE PROCEDURES"); and

d. Complete monthly (or more frequently as reasonably requested by the applicable rating agency) preferred shares basic maintenance test for applicable rating agency(ies) and preferred rate auction following the Compliance Procedures.

SECTION 1.3 RECORDS.

The Agent shall create and maintain all records relating to its activities and obligations under this Agreement in such a manner as will meet the obligations of each Fund under the 1940 Act, specifically Section 31 thereof and Rules 31a-l and 31a-2 thereunder. All such records shall be the property of the applicable Fund and shall at all times during the regular business hours of the Agent be open for inspection by duly authorized officers, employees or agents of the applicable Fund and employees and agents of the Securities and Exchange Commission. Subject to Section 3 below, the Agent shall preserve for the period required by law the records required to be maintained thereunder.

SECTION 1.4 APPOINTMENT OF AGENTS.

The Agent may at its own expense employ agents in the performance of its duties and the exercise of its rights under this Agreement, provided that the employment of such agents shall not reduce the Agent's obligations or liabilities hereunder.

SECTION 2. DUTIES OF EACH FUND.

SECTION 2.1 DELIVERY OF INFORMATION.

Each Fund shall provide, or shall cause a third party to provide, timely notice to the Agent of certain data as a condition to the Agent's performance described in Section 1 above. The data required to be provided pursuant to this section is set forth on Schedule A hereto, which schedule may be separately amended or supplemented by the parties from time to time.

3.


The Agent is authorized and instructed to rely upon the information it receives from the Fund or any third party. The Agent shall have no responsibility to review, confirm or otherwise assume any duty with respect to the accuracy or completeness of any data supplied to it by or on behalf of any Fund.

SECTION 2.2 PROPER INSTRUCTIONS.

The Fund or any other person duly authorized by the Fund shall communicate to the Agent by means of Proper Instructions. Proper Instructions shall mean (i) a writing signed or initialed by one or more persons as the Board of Directors or Board of Trustees of a Fund shall have from time to time authorized or (ii) communication effected directly between a Fund or its third-party agents (each, a "THIRD PARTY AGENT") and the Agent by electro-mechanical or electronic devices, provided that such Fund and the Agent agree to security procedures. The Agent may rely upon any Proper Instruction believed by it to be genuine and to have been properly issued by or on behalf of the applicable Fund. Oral instructions shall be considered Proper Instructions if the Agent reasonably believes them to have been given by a person authorized to give such instructions. The Fund shall cause all oral instructions to be confirmed in accordance with clauses (i) or (ii) above, as appropriate. The Fund shall give timely Proper Instructions to the Agent in regard to matters affecting accounting practices and the Agent's performance pursuant to this Agreement.

SECTION 3. STANDARD OF CARE: LIMITATION OF LIABILITY: EXCLUSIVE REMEDY.

The Agent shall be held to the exercise of reasonable care in carrying out the provisions of this Agreement, but shall be kept indemnified by the Funds, and shall be without liability for any action taken or omitted by it (including, without limitation, acting in accordance with any Proper Instruction) in good faith without willful misconduct or negligence. The Agent shall be entitled to rely on and may act upon the advice of counsel (who may be counsel for the Fund) or the independent accountants for the Fund on all matters, and shall be without liability for any action reasonably taken or omitted pursuant to such advice. Nothing in this paragraph shall be construed as imposing upon the Agent any obligation to seek such instructions or advice, or to act in accordance with such advice when received. Without in any way limiting the generality of the foregoing, the Agent shall in no event be liable for any loss or damage arising from causes beyond its control including, without limitation, delay or cessation of services hereunder or any damages resulting therefrom as a result of work stoppage, power or other mechanical failure, natural disaster, governmental action, communication disruption or other impossibility of performance.

The Agent shall in no event be liable for any special, indirect, incidental, or consequential damages of any kind whatsoever (including, without limitation, attorney's fees) in any way due to a Fund's use of the administration or accounting services or the performance of or failure to perform the Agent's obligations under this Agreement.

4.


Each Fund, any Third Party Agent or Authorized Price Sources from which the Agent shall receive or obtain certain records, reports and other data utilized or included in the services provided hereunder are solely responsible for the contents of such information including, without limitation, the accuracy thereof and each Fund agrees to make no claim against the Agent arising out of the contents of such third-party data including, but not limited to, the accuracy thereof. The Agent shall have no responsibility to review, confirm or otherwise assume any duty with respect to the accuracy or completeness of any such information and shall be without liability for any loss or damage suffered as a result of the Agent's reasonable reliance on and utilization of such information, except as otherwise required by the Price Source Authorization with respect to the use of data obtained from Authorized Price Sources. The Agent shall have no responsibility and shall be without liability for any loss or damage caused by the failure of any Fund or any Third Party Agent to provide it with the information required by Section 2.1 above. Further, and without in any way limiting the generality of the foregoing, the Agent shall have no liability in respect of any loss, damage or expense suffered by the Fund or any third party, insofar as such loss, damage or expense arises from the performance of the Agent's duties hereunder by reason of the Agent's reliance upon records that were maintained for any Fund by any entity other than the Agent prior to such Fund's appointment of the Agent pursuant to this Agreement.

Each Fund agrees to indemnify and hold the Agent free and harmless from any expense, loss, damage or claim, including reasonable attorney's fees, suffered by the Agent and caused by or resulting from the acts or omissions of such Fund or any third-party whose services the Agent must rely upon in performing services hereunder.

Each Fund acknowledges and agrees that, with respect to investments it maintains with an entity which may from time to time act as a transfer agent for uncertificated shares of registered investment companies (the "UNDERLYING TRANSFER AGENT), such Underlying Transfer Agent is the sole source of information on the number of shares held by it on behalf of a Fund and that the Agent has the right to rely on holdings information furnished by the Underlying Transfer Agent to the Agent in performing its duties under this Agreement.

SECTION 3A. PERFORMANCE GOALS.

The Funds and the Agent may from time to time agree on the manner in which they expect to deliver and receive the services contemplated by this Agreement. The parties agree that such agreement(s) (hereinafter referred to as "SERVICE LEVEL DOCUMENTS)") reflect performance goals and any failure to perform in accordance with the provisions thereof shall not be considered a breach of contract that gives rise to contractual or other remedies. It is the intention of the parties that the sole remedy for failure to perform in accordance with the provisions of a Service Level Document, or any dispute relating to performance goals set forth in a Service Level Document, will be a meeting of the parties to resolve the failure pursuant to the consultation procedure described in Sections 3A.1 and 3A.2 below.

SECTION 3A.1. CONSULTATION PROCEDURE. If a party hereto is consistently unable to meet the provisions of a Service Level Document, or in the event that a dispute arises relating to

5.


performance goals set forth in a Service Level Document, either party to this Agreement shall address any concerns it may have by requiring a consultation with the other party.

SECTION 3A.2 PURPOSE OF CONSULTATION PROCEDURE. The purpose of the consultation procedure is to endeavor to resolve a consistent failure to meet the provisions of a Service Level Document. If a consultation occurs under this
Section 3A, all parties must negotiate in good faith to endeavor to:

(a) implement changes which will enable the Service Level Document provisions to be more regularly met;

(b) agree to alternative Service Level Document provisions which meet the parties' respective business requirements; or

(c) otherwise find a solution such that within 30 days after the consultation, the inability to meet the Service Level Document provisions may be less likely to occur in the future.

SECTION 4. REPRESENTATIONS AND WARRANTIES.

SECTION 4.1 REPRESENTATIONS AND WARRANTIES OP THE AGENT.

The Agent represents and warrants to each Fund that:

a. It is a Massachusetts trust company, duly organized and existing under the laws of The Commonwealth of Massachusetts; and

b. The person executing this Agreement on its behalf has been duly authorized to act on its behalf.

SECTION 4.2 REPRESENTATIONS AND WARRANTIES OF EACH FUND.

Each Fund represents and warrants to the Agent that:

a. It is duly organized, existing and in good standing under the laws of the jurisdiction in which it was formed;

b. It has the power and authority under applicable laws and by its organizational documents to enter into and perform this Agreement;

c. All requisite proceedings have been taken to authorize it to enter into and perform this Agreement;

d. It is an investment company properly registered under the 1940 Act; and

e. A registration statement under the 1940 Act (and if Shares of the Fund are offered publicly, under the Securities Act of 1933, as amended (the "1933 Act")) has been filed and will be effective and remain effective during the term of this Agreement. Each Fund also warrants that as of the effective date of this Agreement, all necessary filings

6.


under the securities laws of the states in which the Fund offers or sells its Shares have been made.

SECTION 5. COMPENSATION OF AGENT.

The Agent shall be entitled to reasonable compensation for its services, expenses, out of pocket costs and disbursements as Agent hereunder, as agreed upon from time to time between the Fund and the Agent.

SECTION 6. TERM OF AGREEMENT.

This Agreement shall become effective as of its execution, shall continue in full force and effect until terminated as hereinafter provided and may be terminated by either party by an instrument in writing delivered or mailed, postage prepaid to the other party, such termination to take effect not sooner than sixty (60) days after the date of such delivery or mailing.

Termination of this Agreement with respect to the coverage of any one particular Fund or Portfolio shall in no way affect the rights and duties under this Agreement with respect to any other Fund or Portfolio.

Upon termination of the Agreement or termination of its coverage with respect to any Fund, such Fund shall pay to the Agent such compensation as may be due as of the date of such termination (or with respect to the applicable Fund with respect to a coverage termination) and shall likewise reimburse the Agent for its costs, expenses and disbursements.

SECTION 7. SUCCESSOR AGENT.

If a successor agent for any Fund shall be appointed by a Fund, the Agent shall upon termination deliver to such successor agent at the office of the Agent all properties of such Fund held by it hereunder. If no such successor agent shall be appointed, the Agent shall at its office upon receipt of Proper Instructions deliver such properties in accordance with such instructions.

SECTION 8. GENERAL.

SECTION 8.1 MASSACHUSETTS LAW TO APPLY. This Agreement shall be governed by, construed and the provisions thereof interpreted under and in accordance with laws of The Commonwealth of Massachusetts excluding that body of law applicable to conflicts of law.

7.


SECTION 8.2 PRIOR AGREEMENTS. This Agreement supersedes and terminates, as of the date hereof, all prior agreements between any Fund and the Agent relating to fund accounting and recordkeeping services regarding such Fund.

SECTION 8.3 ASSIGNMENT. This Agreement may not be assigned by (a) a Fund without the prior written consent of the Agent or (b) by the Agent without the prior written consent of the Funds, except that either party may, without such prior consent, assign to an entity controlling, controlled by or under common control with such party or to a successor of all of or a substantial portion of its business.

SECTION 8.4 INTERPRETIVE AND ADDITIONAL PROVISIONS. In connection with the operation of this Agreement, the Agent and the Funds may from time to time agree on such provisions interpretive of or in addition to the provisions of this Agreement as may in their joint opinion be consistent with the general tenor of this Agreement. Any such interpretive or additional provisions shall be in a writing signed by all parties and shall be annexed hereto, provided that no such interpretive or additional provisions shall contravene any applicable federal or state regulations or any provision of a Fund's governing documents. No interpretive or additional provisions made as provided in the preceding sentence shall be deemed to be an amendment of this Agreement.

SECTION 8.5 ADDITIONAL FUNDS. In the event that any management investment company in addition to those listed on Appendix A hereto desires to have the Agent render services as agent under the terms hereof, it shall so notify the Agent in writing, and if the Agent agrees in writing to provide such services, such management investment company shall become a Fund hereunder and be bound by all terms and conditions and provisions hereof with respect to such Fund.

SECTION 8.6 ADDITIONAL PORTFOLIOS. In the event that any Fund establishes one or more series of Shares in addition to those set forth on Appendix A hereto with respect to which it desires to have the Agent render services as agent under the terms hereof, it shall so notify the Agent in writing, and if the Agent agrees in writing to provide such services, such series of Shares shall become a Portfolio hereunder.

SECTION 8.7 AMENDMENTS. NO amendment to this Agreement shall be effective unless it is in writing and signed by a duly authorized representative or each party. The term "Agreement," as used herein, includes all schedules, addenda, exhibits, appendices and attachments hereto and any future written amendments, modifications, or supplements made in accordance herewith.

SECTION 8.8 REMOTE ACCESS SERVICES ADDENDUM. Each Fund and the Agent hereby agree to the terms of the Remote Access Services Addendum hereto.

SECTION 8.9 SERVICES NOT EXCLUSIVE. Each Fund hereby acknowledges that the services of the Agent hereunder are not to be deemed exclusive to any Fund and the Agent remains free to render similar services to others.

8.


SECTION 8.10 NOTICES. Any notice, instruction or other instrument required to be given hereunder may be delivered in person to the offices of the parties as set forth herein during normal business hours or delivered prepaid registered mail or by telex, cable or telecopy to the parties at the following addresses or such other addresses as may be notified by any party from time to time.

To any Fund: c/o Calamos Asset Management, Inc. 111 East Warrenville Road
Naperville, Illinois 60563-1493 Attention: _________________, Treasurer Telephone: (630) 577-2106
Telecopy: (630)955-6964

To the Agent: STATE STREET BANK AND TRUST COMPANY

Joseph Palmer Building

One Heritage Drive, JPB3N
North Quincy, Massachusetts 02171 Attention: Scott E. Johnson, Vice President Telephone: 617-985-6725
Telecopy: 617-985-9797

Such notice, instruction or other instrument shall be deemed to have been served in the case of a registered letter at the expiration of five business days after posting, in the case of cable twenty-four hours after dispatch and, in the case of telex, immediately on dispatch and if delivered outside normal business hours it shall be deemed to have been received at the next time after delivery when normal business hours commence and in the case of cable, telex or telecopy on the business day after the receipt thereof. Evidence that the notice was properly addressed, stamped and put into the post shall be conclusive evidence of posting.

SECTION 8.11 HEADINGS NOT CONTROLLING. Headings used in this Agreement are for reference purposes only and shall not be deemed a part of this Agreement.

SECTION 8.12 SURVIVAL. All provisions regarding indemnification, warranty, liability and limits thereon shall survive the expiration or termination of this Agreement.

SECTION 8.13 COUNTERPARTS. This Agreement may be executed in several counterparts, each of which shall be deemed to be an original, and all such counterparts taken together shall constitute one and the same agreement.

SECTION 8.14 SEVERABILITY. If any provision or provisions of this Agreement shall be held to be invalid, unlawful or unenforceable, the validity, legality and enforceability of the remaining provisions shall not in any way be affected or impaired.

9.


SECTION 8.15 REPRODUCTION OF DOCUMENTS. This Agreement and all schedules, addenda, exhibits, appendices, attachments and amendments hereto may be reproduced by any photographic, photostatic, microfilm, micro-card, miniature photographic or other similar process. The parties hereto all/each agree that any such reproduction shall be admissible in evidence as the original itself in any judicial or administrative proceeding, whether or not the original is in existence and whether or not such reproduction was made by a party in the regular course of business, and that any enlargement, facsimile or further reproduction of such reproduction shall likewise be admissible in evidence.

REMAINDER OF PAGE INTENTIONALLY LEFT BLANK

10.


SIGNATURE PAGE

IN WITNESS WHEREOF, each of the parties has caused this instrument to be executed in its name and behalf by its duly authorized representative and its seal to be hereunder affixed as of the date first above-written.

SIGNATURE ATTESTED TO BY:               EACH REGISTERED MANAGEMENT INVESTMENT
                                        COMPANY SET FORTH ON APPENDIX A HERETO


                                        By:
-------------------------------------       ------------------------------------
Ian J. McPheron, Assistant Secretary        Nimish Bhatt, Treasurer


SIGNATURE ATTESTED TO BY:               STATE STREET BANK AND TRUST COMPANY


                                        By:
-------------------------------------       ------------------------------------
Stephanie L. Poster, Vice President         Joseph L. Hooley, Executive
                                            Vice President


APPENDIX A
TO
MASTER ACCOUNTING SERVICES AGREEMENT

MANAGEMENT INVESTMENT COMPANIES AND PORTFOLIOS THEREOF, IF ANY

CALAMOS STRATEGIC TOTAL RETURN FUND

(i)

EXHIBIT A
TO
MASTER ACCOUNTING SERVICES AGREEMENT

FORM OF PRICE SOURCE AUTHORIZATION

(i)

To: State Street Bank and Trust Company

From: Fund Name: __________________________________________

Fund Address: _____________________________________________

Date: ______________

Re: PRICE SOURCE AUTHORIZATION

Reference is made to that certain Master Administration and Accounting Services Agreement dated March 15, 2004 (as amended, restated, modified or supplemented from time to time, the "Agreement") by and among each Fund and the Agent. Capitalized terms used in this Price Source Authorization or in any attachment or supplement shall have the meanings provided in the Agreement unless otherwise specified. Pursuant to the Agreement, each Fund hereby directs the Agent to calculate the net asset value ("NAV") of such Fund or, if applicable, its Portfolios, in accordance with the terms of such Fund's or Portfolio's currently effective prospectus. The Agent will perform the NAV calculation subject to the terms and conditions of the Agreement and this Price Source Authorization.

Each Fund hereby authorizes the Agent to use the pricing sources specified on the attached Authorization Matrix (as amended from time to time) as sources for prices of assets in calculating the NAV of such Fund. Each Fund understands that the Agent does not assume responsibility for the accuracy of the quotations provided by the specified pricing sources and that the Agent shall have no liability for any incorrect data provided by the pricing sources specified by any Fund, except as may arise from the Agent's lack of reasonable care in performing agreed upon tolerance checks as to the data furnished and calculating the NAV of a Fund in accordance with the data furnished to the Agent. Each Fund also acknowledges that prices supplied by such Fund or an affiliate may be subject to approval of that Fund's Board of Trustees or Board of Directors, as applicable, and are not the responsibility of the Agent.

Each Fund agrees to Indemnify and hold the Agent harmless from any claim, loss or damage arising as a result of using prices furnished by any specified pricing source.

The Agent agrees that written notice of any change in the name of any specified pricing source will be sent to affected Fund as such information is available to the Agent.

Kindly acknowledge your acceptance of this authorization in the space provided below.

EACH FUND LISTED ON APPENDIX A HERETO

By:                                     The foregoing authorization is hereby
    ---------------------------------   accepted.
Name:
      -------------------------------    STATE STREET BANK AND TRUST COMPANY
Title:
       ------------------------------
                                        By:
                                            ------------------------------------
                                                                 ,Vice President


APPENDIX A

[LIST OF FUNDS]


SCHEDULE A
TO
MASTER ACCOUNTING SERVICES AGREEMENT

INFORMATION REQUIRED TO BE SUPPLIED        RESPONSIBLE PARTY
-----------------------------------        -----------------
Portfolio Trade Authorizations             Investment Adviser
Currency Transactions                      Investment Adviser
Cash Transaction Report                    Custodian
Portfolio Prices                           Third Party Vendors/Investment Adviser
Exchange Rates                             Third Party Vendors/Investment Adviser
Capital Stock Activity Report              Transfer Agent
Dividend/Distribution Schedule             Investment Adviser
Dividend/Distribution Declaration          Investment Adviser
Dividend Reconciliation/Confirmation       Transfer Agent
Corporate Actions                          Third Party Vendors/Custodian
Service Provider Fee Schedules             Investment Adviser
Expense Budget                             Investment Adviser/Administrator
Amortization Policy                        Investment Adviser
Accounting Policy/Complex Investments      Investment Adviser
Audit Management Letter                    Auditor
Annual Shareholder Letter                  Investment Adviser
Annual/Semi-Annual Reports                 Investment Adviser/Administrator
Declaration of Trust or Articles           Investment Adviser/Administrator
   of incorporation, as amended
By-Laws, as amended                        Investment Adviser/Administrator
Currently Effective Registration           Investment Adviser/Administrator
   Statement under the 1933 and 1940 Act
Current Prospectus(es) and Statement(s)    Investment Adviser/Administrator
   of Additional Information
Such other certificates, documents or      Investment Adviser/Administrator
   opinions which the Agent may, in its
   reasonable discretion, deem necessary
   or appropriate in the proper
   performance of its duties

(i)

REMOTE ACCESS SERVICES ADDENDUM
TO
MASTER ADMINISTRATION AND ACCOUNTING SERVICES AGREEMENT

ADDENDUM to that certain Master Administration and Accounting Services Agreement dated as of March 15, 2004 (the "Agreement") by and among each registered management investment company identified on Appendix A thereto and made subject thereto pursuant to Section 9.5 thereof (each, a "Customer") and State Street Bank and Trust Company, including its subsidiaries and affiliates ("State Street").

State Street has developed and utilizes proprietary accounting and other systems in conjunction with the services which State Street provides to the Customer. In this regard, State Street maintains certain information in databases under its control and ownership which it makes available to its customers (the "Remote Access Services").

The Services

State Street agrees to provide the Customer, and its designated investment advisors, consultants or other third parties authorized by State Street ("Authorized Designees") with access to In-Sight(SM) as described in Exhibit A or such other systems as may be offered from time to time (the "System") on a remote basis.

Security Procedures

The Customer agrees to comply, and to cause its Authorized Designees to comply, with remote access operating standards and procedures and with user identification or other password control requirements and other security procedures as may be issued from time to time by State Street for use of the System and access to the Remote Access Services. The Customer agrees to advise State Street immediately in the event that it learns or has reason to believe that any person to whom it has given access to the System or the Remote Access Services has violated or intends to violate the terms of this Addendum and the Customer will cooperate with State Street in seeking injunctive or other equitable relief. The Customer agrees to discontinue use of the System and Remote Access Services, if requested, for any security reasons cited by State Street.

Fees

Fees and charges for the use of the System and the Remote Access Services and related payment terms shall be as set forth in the fee schedule in effect from time to time between the parties. The Customer shall be responsible for any tariffs, duties or taxes imposed or levied by any government or governmental agency by reason of the transactions contemplated by this Addendum, including, without limitation, federal, state and local taxes, use, value added and personal property taxes (other than income, franchise or similar taxes which may be imposed or assessed against State Street). Any claimed exemption from such tariffs, duties or taxes shall be supported by proper documentary evidence delivered to State Street.

Proprietary Information/Injunctive Relief

The System and Remote Access Services described herein and the databases, computer programs, screen formats, report formats, interactive design techniques, formulae, processes, systems, software, know-how, algorithms, programs, training aids, printed materials, methods, books, records, files, documentation and other information made available to the Customer by State Street as part of the Remote Access Services and through the use of the System and all copyrights, patents, trade secrets and


other proprietary rights of State Street related thereto are the exclusive, valuable and confidential property of State Street and its relevant licensors (the "Proprietary Information"). The Customer agrees on behalf of itself and its Authorized Designees to keep the Proprietary Information confidential and to limit access to its employees and Authorized Designees (under a similar duty of confidentiality) who require access to the System for the purposes intended. The foregoing shall not apply to Proprietary Information in the public domain or required by law to be made public.

The Customer agrees to use the Remote Access Services only in connection with the proper purposes of this Addendum. The Customer will not, and will cause its employees and Authorized Designees not to, (i) permit any third party to use the System or the Remote Access Services, (ii) sell, rent, license or otherwise use the System or the Remote Access Services in the operation of a service bureau or for any purpose other than as expressly authorized under this Addendum, (iii) use the System or the Remote Access Services for any fund, trust or other investment vehicle without the prior written consent of State Street, or (iv) allow or cause any information transmitted from State Street's databases, including data from third party sources, available through use of the System or the Remote Access Services, to be published, redistributed or retransmitted for other than use for or on behalf of the Customer, as State Street's customer.

The Customer agrees that neither it nor its Authorized Designees will modify the System in any way; enhance or otherwise create derivative works based upon the System, nor will your or your Authorized Designees reverse engineer, decompile or otherwise attempt to secure the source code for all or any part of the System.

The Customer acknowledges that the disclosure of any Proprietary Information, or of any information which at law or equity ought to remain confidential, will immediately give rise to continuing irreparable injury to State Street inadequately compensable in damages at law and that State Street shall be entitled to obtain immediate injunctive relief against the breach or threatened breach of any of the foregoing undertakings, in addition to any other legal remedies which may be available.

Limited Warranties

State Street represents and warrants that it is the owner of and has the right to grant access to the System and to provide the Remote Access Services contemplated herein. Because of the nature of computer information technology including, but not limited to, the use of the Internet, and the necessity of relying upon third party sources, and data and pricing information obtained from third parties, the System and Remote Access Services are provided "AS IS", and the Customer and its Authorized Designees shall be solely responsible for the investment decisions, results obtained, regulatory reports and statements produced using the Remote Access Services. State Street and its relevant licensors will not be liable to the Customer or its Authorized Designees for any direct or indirect, special, incidental, punitive or consequential damages arising out of or in any way connected with the System or the Remote Access Services, nor shall either party be responsible for delays or nonperformance under this Addendum arising out of any cause or event beyond such party's control.

State Street will take reasonable steps to ensure that its products (and those of its third-party suppliers) reflect the available state of the art technology to offer products that are Year 2000 compliant, including, but not limited to, century recognition of dates, calculations that correctly compute same century and multi century formulas and date values, and interface values that reflect the date issues arising between now and December 31, 2099, and if any changes are required, State Street will make the changes to its products at no cost to you and in a commercially reasonable time frame and will require third-party suppliers to do likewise. The Customer will do likewise for its systems.

ii

EXCEPT AS EXPRESSLY SET FORTH IN THIS ADDENDUM, STATE STREET, FOR ITSELF AND ITS RELEVANT LICENSORS, EXPRESSLY DISCLAIMS ANY AND ALL WARRANTIES CONCERNING THE SYSTEM AND THE SERVICES TO BE RENDERED HEREUNDER, WHETHER EXPRESS OR IMPLIED INCLUDING, WITHOUT LIMITATION, ANY WARRANTY OF MERCHANTIBILITY OR FITNESS FOR A PARTICULAR PURPOSE.

Infringement

State Street will defend or, at our option, settle any claim or action brought against the Customer to the extent that it is based upon an assertion that access to the System or use of the Remote Access Services by the Customer under this Addendum constitutes direct infringement of any patent or copyright or misappropriation of a trade secret, provided that the Customer notifies State Street promptly in writing of any such claim or proceeding and cooperates with State Street in the defense of such claim or proceeding. Should the System or the Remote Access Services or any part thereof become, or in State Street's opinion be likely to become, the subject of a claim of infringement or the like under any applicable patent or copyright or trade secret laws, State Street shall have the right, at State Street's sole option, to (i) procure for the Customer the right to continue using the System or the Remote Access Services,
(ii) replace or modify the System or the Remote Access Services so that the System or the Remote Access Services becomes noninfringing, or (iii) terminate this Addendum without further obligation.

Termination

Either party to the Agreement may terminate this Addendum (i) for any reason by giving the other party at least one-hundred and eighty (180) days prior written notice in the case of notice of termination by State Street to the Customer or thirty (30) days notice in the case of notice from the Customer to State Street of termination, or (ii) immediately for failure of the other party to comply with any material term and condition of the Addendum by giving the other party written notice of termination. This Addendum shall in any event terminate within ninety (90) days after the termination of the Agreement. In the event of termination, the Customer will return to State Street all copies of documentation and other confidential information in its possession or in the possession of its Authorized Designees. The foregoing provisions with respect to confidentiality and infringement will survive termination for a period of three
(3) years.

Miscellaneous

This Addendum and the exhibit hereto constitute the entire understanding of the parties to the Agreement with respect to access to the System and the Remote Access Services. This Addendum cannot be modified or altered except in a writing duly executed by each of State Street and the Customer and shall be governed by and construed in accordance with the laws of The Commonwealth of Massachusetts.

By its execution of the Agreement, the Customer (a) confirms to State Street that it informs all Authorized Designees of the terms of this Addendum; (b) accepts responsibility for its and its Authorized Designees' compliance with the terms of this Addendum; and (c) indemnifies and holds State Street harmless from and against any and all costs, expenses, losses, damages, charges, counsel fees, payments and liabilities arising from any failure of the Customer or any of its Authorized Designees to abide by the terms of this Addendum.

iii

EXHIBIT A
TO
REMOTE ACCESS SERVICES ADDENDUM

IN-SIGHT(SM)
System Product Description

In-Sight(SM) provides bilateral information delivery, interoperability, and on-line access to State Street. In-Sight(SM) allows users a single point of entry into State Street's diverse systems and applications. Reports and data from systems such as Investment Policy Monitor(SM), Multicurrency Horizon(SM), Securities Lending, Performance & Analytics and Electronic Trade Delivery can be accessed through In-Sight(SM). This Internet-enabled application is designed to run from a Web browser and perform across low-speed data lines or corporate high-speed backbones. In-Sight(SM) also offers users a flexible toolset, including an ad-hoc query function, a custom graphics package, a report designer, and a scheduling capability. Data and reports offered through In-Sight(SM) will continue to increase in direct proportion with the customer roll out, as it is viewed as the information delivery system will grow with State Street's customers.

iv

October 28, 2004

State Street Bank and Trust Company
225 Franklin Street
Boston, MA 02110
Attention: Scott E. Johnson, Vice President, JPB3N Thresa B. Dewar, Vice President, LCC4

Re: Calamos Global Total Return Fund (the "FUND")

Ladies and Gentlemen:

Please be advised that the undersigned Fund has been incorporated and registered as a management investment company under the Investment Company Act of 1940, as amended.

In accordance with Section 8.5, the Additional Funds provision, of the Master Services Agreement dated as of March 15, 2004 by and among each registered management investment company party thereto and State Street Bank and Trust Company (the "CONTRACT"), the undersigned Fund hereby requests that your bank act as Agent (as such term is defined in the Contract) for the Fund under the terms of the Contract. In connection with such request, the undersigned Fund hereby confirms to you, as of the date hereof, its representations and warranties set forth in Section 4.2 of the Contract.

Kindly indicate your acceptance of the foregoing by executing two copies of this letter agreement, returning one to the Fund and retaining one for your records.

Sincerely,

Calamos Global Total Return Fund

By: /s/ Nimish Bhatt
    ------------------------------------
Name: Nimish Bhatt
Title: Treasurer, Duly Authorized

AGREED AND ACCEPTED:

STATE STREET BANK AND TRUST COMPANY

By: /s/ Joseph L. Hooley
    ---------------------------------
Name: Joseph L. Hooley
Title: Executive Vice President,
       Duly Authorized

Effective Date: October 28, 2004


October 31, 2004

State Street Bank and Trust Company
225 Franklin Street
Boston, Massachusetts 02110
Attention: Scott E. Johnson, Vice President, JPB3N Thresa B. Dewar, Vice President, LCC4

Ladies and Gentlemen:

Reference is made to that certain Master Services Agreement by and among the Agent and each Fund dated as of March 15,2004 (as amended, restated, modified or supplemented from time to time, the "AGREEMENT"). Capitalized terms used herein and not otherwise defined shall have the meanings given to such terms in the Agreement.

Reference is further made to that certain letter agreement by and among the Agent and each Fund party thereto (by virtue of its status as a party to the Agreement) dated as of March 15, 2004 (as amended, restated, modified or supplemented from time to time, the "FIRST SIDE LETTER").

Reference is finally made to Calamos Convertible Opportunities and Income Fund, Calamos Convertible and High Income Fund and Calamos Global Total Return Fund (collectively, the "ADDITIONAL FUNDS").

For good and valuable consideration, the receipt and sufficiency of which is hereby acknowledged, each Fund hereby requests the Agent's consent to the terms and provisions of this letter agreement (the "SECOND SIDE LETTER").

1. Application to All Funds. For the avoidance of doubt, each Fund does hereby acknowledge and confirm to the Agent that the First Side Letter does, and this Second Side Letter shall, each apply for their respective periods of coverage on a cumulative and aggregate basis to all of the Funds.

2. Cap on Potential Liability of Agent. In the event that each of the Additional Funds has retained the Agent to perform services under the Agreement on or before the date hereof (via their due execution of additional fund letter(s) in the manner set forth in Section 8.5 of the Agreement), then commencing on November 1, 2004, pursuant to Section 3 of the Agreement, the Agent's cumulative liability for each calendar year with respect to the Funds, regardless of the form of action or legal theory, shall be limited to actual or direct damage up to the greater of (i) one (1) times its total compensation earned and fees payable under the Agreement during the calendar year (or annualized period) preceding the event giving liability or (ii) Seven Million Five Hundred Thousand Dollars ($7,500,000.00). It being specifically understood by each Fund that in the event that all of the Additional Funds have not retained the Agent as set forth above, the Agent's potential liability shall remain as originally capped by the First Side Letter.


State Street Bank and Trust Company
October 31, 2004

Page 2

3. Continuing Coverage of First Side Letter. In any event, and even in the event that each of the Additional Funds have retained the Agent as set forth above, the terms and provisions of the First Side Letter including, the cumulative cap on Agent's liability imposed thereby shall continue govern all events or circumstances, if any, which have or may arise or occur from the period from March 15, 2004 through the date hereof and give rise to the Agent's liability, even if any such event or occurrence becomes known after the date hereof and/or continues to give rise to Agent liability beyond the date hereof.

4. Confidentiality. Each Fund agrees that it shall keep the provisions of the First Side Letter and this Second Side Letter confidential and shall not disclose the same to any other person or entity other than a regulator of any Fund (as such regulator may require), and except at the request, or with the prior written consent, of the Agent.

5. Captions. The captions herein have been inserted solely for convenience or reference and in no way define, limit or describe the scope or substance of any provision of the First Side Letter or this Second Side Letter.

If the foregoing is acceptable to you, kindly indicate your consent by executing the enclosed duplicate original copy of this Second Side Letter. This instrument is executed under seal as of the date and year first above-written and shall be governed by, and construed in accordance with, the laws of The Commonwealth of Massachusetts.

Sincerely,

EACH REGISTERED MANAGEMENT
INVESTMENT COMPANY PARTY TO THE
AGREEMENT

By: /s/ Nimish Bhatt
    ------------------------------------
    Nimish Bhatt,
    Treasurer, Duly Authorized

ACCEPTED AND AGREED:

STATE STREET BANK AND TRUST COMPANY

By: /s/ Joseph L. Hooley
    ---------------------------------
    Joseph L. Hooley,
    Executive Vice President


FEE SCHEDULE FOR
CALAMOS CONVERTIBLE OPPORTUNITIES AND INCOME FUND
CALAMOS CONVERTIBLE AND HIGH INCOME FUND
CALAMOS STRATEGIC TOTAL RETURN FUND
STATE STREET BANK AND TRUST COMPANY


I. FUND ACCOUNTING AND ADMINISTRATION

a. Maintain each Portfolio's general ledger and such other accounts, books and financial records of such Portfolio as the parties may agree upon from time to time, and as may be required by the Investment Company Act of 1940, as amended (the "1940 ACT");

b. Maintain each Portfolio's portfolio security transaction records utilizing trade date provided to the Agent by such Portfolio's duly authorized investment adviser (each, an "INVESTMENT ADVISOR");

c. For each valuation date, post each Portfolio's transactions to such Portfolio general ledger including, but not limited to:

-Calculate unrealized appreciation and depreciation regarding portfolio securities;

-Amortize premiums and accrete discounts regarding portfolio securities, as applicable;

-Calculate fee-based expenses and set-up expense accruals as directed by the applicable fund

-Record payments of Portfolio expenses upon written instructions of a Fund or duly authorized agent thereof;

-Calculate interest and dividend income and reset interest accrual for variable rate securities, as applicable.

d. Reconcile cash, foreign currency and portfolio security holding positions with each Portfolio's custodian (each, a "CUSTODIAN") daily;

e. Post each Portfolio's corporate actions;

f. Calculate the net asset value of each Portfolio and report same to the Fund or such other entities or persons as the Fund may instruct from time to time;

g. Prepare and transmit to the Fund, or such other entities or persons as the Fund may instruct from time to time, such periodic reports of Fund data as may be mutually agreed upon by the parties hereto; and Post shareholder reinvestment activity and reconcile share balances with each Portfolio's transfer agent (each, a "TRANSFER AGENT") in conjunction with Portfolio distributions.

h.

i. Prepare monthly distribution analysis


j. Complete monthly preferred shares "asset coverage" test (as the term is defined in Section 18(h) of the 1940 Act following agreed-upon compliance procedures (the "COMPLIANCE PROCEDURES"); and

k. Complete monthly (or more frequently as reasonably requested by the applicable rating agency) preferred shares basic maintenance test for applicable rating agency(ies) and preferred rate auction following the Compliance Procedures.

THE FEE SHOWN BELOW IS ANNUALIZED, BILLED AND PAYABLE MONTHLY AND
BASED ON THE MANAGED ASSETS OF THE FUND.

COMPLEX WIDE MANAGED ASSETS                          ANNUAL FEES
----------------------------------------------------------------
$0-$1.5 billion                                          1.75 BP
$1.5-$3.0 billion                                        1.50 BP
$3.0-$4.5 billion                                        1.25 BP
$4.5-$6.0 billion                                        1.00 BP
$6.0-$7.5 billion                                        .750 BP
Excess                                                   .375 BP

Fund Minimums WAIVED ON EXISTING OR FILED MUTUAL FUNDS, A TOTAL OF 13
FUNDS

         Open-end funds                                  $40,000 Annual Minimum
         Closed-end funds                                $50,000 Annual Minimum



II.   SPECIAL SERVICES
--------------------------------------------------------------------------------

Fees for activities of a non-recurring nature such as fund consolidations or reorganizations, extraordinary security shipments and the preparation of special reports will be subject to negotiation.


III. OUT-OF-POCKET EXPENSES

A billing for the recovery of applicable out-of-pocket expenses will be made as of the end of each month. These out-of-pocket expenses may be adjusted based on market conditions or other circumstances. Out-of-pocket fees include, but are not limited to the following examples:

-Communications/equipment costs (telephone, lease lines etc.) -Postage, courier service and insurance -Duplicating
-Non recurring legal fees
-Archiving fund records
-Travel and lodging to operation meetings -Customized programming/transmission @ $120 per hour (first 200 hours for free)
-Annual maintenance fee for each customized program/transmission ($3,000) waived


V. TERMS OF FEE SCHEDULE

The parties agree that the fee schedule shall remain in effect until December 31, 2005, or until the Master Services Agreement is terminated. The fee schedule will continue from year to year thereafter until it is revised as a result of negotiations initiated by either party.



VI. PAYMENT

All fees above will be invoiced to the Funds by the fifth business day. Management of the Funds will review and authorize the Custodian bank to send the payment to State Street by the 15th of the month. Payment does not preclude any required billing adjustments that will be made to the following month's bill.

EACH REGISTERED MANAGEMENT STATE STREET BANK AND TRUST COMPANY
INVESTMENT COMPANY PARTY TO THE
AGREEMENT

BY:     NIMISH BLATT                      BY:    [ILLEGIBLE]
        ---------------                          ------------------------
TITLE:  Treasurer                         TITLE: Vice President
        ---------------                          ------------------------
DATE:   10/22/04                          DATE:  10/29/04
        ---------------                          ------------------------


EXHIBIT n

CONSENT OF INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM

We consent to the use in this Pre-Effective Amendment No. 4 to Registration Statement No. 333-114111 of CALAMOS Global Total Return Fund on Form N-2 of our report dated October 25, 2005, appearing in the Prospectus, which is part of such Registration Statement. We also consent to the reference under the caption "Experts" in the Statement of Additional Information, which is also part of such Registration Statement.

/S/ DELOITTE & TOUCHE LLP

Chicago, Illinois
October 25, 2005


Exhibit p

CALAMOS GLOBAL TOTAL RETURN FUND

SUBSCRIPTION AGREEMENT

This Agreement made October 17, 2005 by and between Calamos Global Total Return Fund, a Delaware statutory trust (the "Fund"), and Calamos Advisors LLC, a limited liability company of the state of Delaware(the "Subscriber");
WITNESSETH:

WHEREAS, the Fund has been formed for the purposes of carrying on business as a closed-end diversified management investment company;

WHEREAS, the Subscriber has been selected by the Fund's Board of Trustees to serve as investment adviser to the Fund; and WHEREAS, the Subscriber wishes to subscribe for and purchase, and the Fund wishes to sell to the Subscriber, 6,980.80 common shares for a purchase price of $14.325 per share.
NOW THEREFORE, IT IS AGREED:
1. The Subscriber subscribes for and agrees to purchase from the Fund 6,980.80 common shares for a purchase price of $14.325 per share. Subscriber agrees to make payment for these shares at such time as demand for payment may be made by an officer of the Fund.
2. The Fund agrees to issue and sell said shares to Subscriber promptly upon its receipt of the purchase price.

3. To induce the Fund to accept its subscription and issue the shares subscribed for, the Subscriber represents that it is informed as follows:

(a) That the shares being subscribed for have not been and will not be registered under the Securities Act of 1933 ("Securities Act");

(b) That the shares will be sold by the Fund in reliance on an exemption from the registration requirements of the Securities Act;

(c) That the Fund's reliance upon an exemption from the registration requirements of the Securities Act is predicated in part on the representation and agreements contained in this Subscription Agreement;

(d) That when issued, the shares will be "restricted securities" as defined in paragraph (a)(3) of Rule 144 of the General Rules and Regulations under the Securities Act ("Rule 144") and cannot be sold or transferred by Subscriber unless they are subsequently registered under the Securities Act or unless an exemption from such registration is available; and

1.


(e) That there do not appear to be any exemptions from the registration provisions of the Securities Act available to the Subscriber for resale for the shares. In the future, certain exemptions may possibly become available, including an exemption for limited sales including an exemption for limited sales in accordance with the conditions of Rule 144.

The Subscriber understands that a primary purpose of the information acknowledged in subparagraphs (a) through (e) above is to put it on notice as to restrictions on the transferability of the shares.

4. To further induce the Fund to accept its subscription and issue the shares subscribed for, the Subscriber:

(a) Represents and warrants that the shares subscribed for are being and will be acquired for investment for its own account and not on behalf of any other person or persons and not with a view to, or for sale in connection with, any public distribution thereof;

(b) Agrees that any certificates representing the shares subscribed for may bear a legend substantially in the following form:

The shares represented by this certificate have been acquired for investment and have not been registered under the Securities Act of 1933 or any other federal or state securities law. These shares may not be offered for sale, sold or otherwise transferred unless registered under said securities laws or unless some exemption from registration is available.

(c) Consents, as the sole holder of the Trust's common shares of beneficial interest and pursuant to Section 23(b)(2) of the Investment Company Act of 1940, to the issuance by the Trust of common shares of beneficial interest at a price per share as set forth in the Purchase Agreement relating to the public offering of Shares; and

5. This Subscription Agreement and all of its provisions shall be binding upon the legal representatives, heirs, successors and assigns of the parties hereto. This Subscription Agreement may be signed in one or more counterparts, each of which shall be deemed to be an original.

2.


IN WITNESS WHEREOF, this Subscription Agreement has been executed by the parties hereto as of the day and date first above written.

CALAMOS GLOBAL TOTAL RETURN FUND

By: /S/ JAMES S. HAMMAN, JR.
    -------------------------------------
    James S. Hamman, Jr., Secretary

CALAMOS ADVISORS LLC

By: /S/ PATRICK DUDASIK
    -------------------------------------
    Patrick Dudasik,
    Executive Vice President

3.