ARTICLE I

DESCRIPTION OF THE SERIES DD MORTGAGE BONDS.

THE TRUSTEE.

MISCELLANEOUS PROVISIONS.

Name:

Jerre E. Birdsong

Name:

Jerre E. Birdsong

ARTICLE I

DESCRIPTION OF THE SERIES DD MORTGAGE BONDS.

THE TRUSTEE.

MISCELLANEOUS PROVISIONS.

Section 1. The Company hereby creates a new series of Bonds to be known as “Mortgage Bonds, Senior Notes Series DD” (the “Series DD Mortgage Bonds”). The Series DD Mortgage Bonds shall be executed, authenticated and delivered in accordance with the provisions of, and shall in all respects be subject to, all of the terms, conditions and covenants of the Indenture, as supplemented and modified. The Series DD Mortgage Bonds shall be issued in the name of the Senior Note Trustee under the Senior Note Indenture to secure any and all of the Company’s obligations under the Senior Notes and any other series of senior notes from time to time outstanding under the Senior Note Indenture.

Section 2. The Series DD Mortgage Bonds and the Trustee’s Certificate of Authentication shall be substantially in the following forms respectively:

Section 2. The Series DD Mortgage Bonds and the Trustee’s Certificate of Authentication shall be substantially in the following forms respectively:

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UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

WASHINGTON, D.C. 20549

FORM 8-K

CURRENT REPORT

Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934

Date of Report (Date of earliest event reported):

October 23, 2008

Commission File Number	Exact Name of Registrant as specified in its charter; State of Incorporation; Address and Telephone Number	IRS Employer Identification No.

1-14756	Ameren Corporation	43-1723446
	(Missouri Corporation) 1901 Chouteau Avenue St. Louis, Missouri 63103 (314) 621-3222

1-3004	Illinois Power Company	37-0344645
	(Illinois Corporation) 370 South Main Street Decatur, Illinois 62523 (217) 424-6600

Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions:

o Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425)

o Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12)

o Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b))

o Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c))

Item 2.03.

Creation of a Direct Financial Obligation or an Obligation under an Off-Balance Sheet Arrangement of a Registrant.

On October 23, 2008, Illinois Power Company, d/b/a AmerenIP (“IP”), a subsidiary of Ameren Corporation (“Ameren”), issued and sold $400,000,000 principal amount of its 9.75% Senior Secured Notes due 2018 (the “Notes”) with registration rights in a private placement transaction. The Notes were issued under IP’s Indenture dated as of June 1, 2006 between IP and The Bank of New York Mellon Trust Company, N.A., as trustee (the “Indenture”). The Notes will mature on November 15 , 20 18 . IP will pay interest on the Notes on May 15 and November 15 of each year. The first such payment will be made on May 15 , 2009. IP may at any time and from time to time redeem all or a portion of the Notes at a make-whole redemption price. IP will use the net proceeds from the sale of the Notes to repay its short-term debt consisting of borrowings under its credit facilities and/or under Ameren’s utility money pool arrangement. IP issued a press release with respect to the issuance of the Notes on October 21, 2008, which is included as Exhibit 99.1 to this Current Report on Form 8-K.

The Notes will be secured by a related series of IP’s mortgage bonds issued and delivered by IP to the trustee under the General Mortgage Indenture and Deed of Trust dated as of November 1, 1992, as supplemented by the Supplemental Indenture dated as of October 1, 2008 between IP and The Bank of New York Mellon Trust Company, N.A. (formerly BNY Midwest Trust Company, successor to Harris Trust and Savings Bank), as mortgage trustee (the “Mortgage”). Accordingly, the Notes will be secured ratably with IP’s mortgage bonds in the collateral pledged to secure such bonds.

The Indenture contains default provisions relating to failure to make required payments on any senior secured debt securities of IP when due and payable (including the Notes), default in the performance or breach of any other covenants of IP for 60 days after notice, certain events in bankruptcy, insolvency or reorganization and the occurrence of a default under the Mortgage. The Mortgage contains default provisions relating to failure to make required payments on any outstanding mortgage bonds, default in the performance of other covenants for 60 days after notice and certain events in reorganization, bankruptcy, insolvency or receivership.

If an event of default under the Indenture occurs and is continuing, the trustee under the Indenture, or the holders of 33% of the outstanding senior secured debt securities of IP (including the Notes) , may declare the principal and interest on such senior secured debt securities due and payable immediately. Upon such acceleration, the mortgage bonds securing the Notes and any other mortgage bonds securing senior secured debt securities of IP will be immediately redeemable upon demand of the trustee, and surrender thereof to the mortgage trustee, at a redemption price of 100% of the principal amount thereof, together with interest to the redemption date.

IP has agreed to file an exchange offer registration statement and/or, under certain circumstances, a shelf registration statement pursuant to a registration rights agreement with the initial purchasers of the Notes. If IP fails to comply with certain obligations under the registration rights agreement, it will be required to pay additional interest at the rate of 0.25% per year on the Notes for the period of non-compliance (plus an additional 0.25% per year from and during any period in which such non-compliance continues for more than 90 days, up to a maximum rate of 0.50% per year).

Item 9.01.		Financial Statements and Exhibits.

	(d)	Exhibits.

		**4.1		Indenture dated as of June 1, 2006, between IP and The Bank of New York Mellon Trust Company, N.A., as trustee, relating to the Notes (Annual Report on Form 10-K for the year ended December 31, 2007, Exhibit 4.101).

		*4.2		Company Order establishing the Notes, including forms of global and definitive notes.

		**4.3		General Mortgage Indenture and Deed of Trust dated as of November 1, 1992 between IP and The Bank of New York Mellon Trust Company, N.A. (formerly BNY Midwest Trust Company, successor to Harris Trust and Savings Bank), as trustee (Annual Report on Form 10-K for the year ended December 31, 2007, Exhibit 4.88).

		*4.4		Supplemental Indenture dated as of October 1, 2008 by and between IP and The Bank of New York Mellon Trust Company, N.A. (formerly BNY Midwest Trust Company), as trustee, relating to the Mortgage Bonds, Senior Notes Series DD securing the Notes.

		*99.1		Press release of IP dated October 21, 2008.

This combined Current Report on Form 8-K is being filed separately by Ameren and IP (each, a “registrant”). Information contained herein relating to any individual registrant has been filed by such registrant on its own behalf. No registrant makes any representation as to information relating to any other registrant.

* Filed herewith.

** Incorporated by reference as indicated.

SIGNATURES

Pursuant to the requirements of the Securities Exchange Act of 1934, each registrant has duly caused this report to be signed on its behalf by the undersigned thereunto duly authorized. The signature for each undersigned company shall be deemed to relate only to matters having reference to such company or its subsidiaries.

AMEREN CORPORATION
(Registrant)

By	/s/ Jerre E. Birdsong
Name:		Jerre E. Birdsong
Title:		Vice President and Treasurer


ILLINOIS POWER COMPANY
(Registrant)

By	/s/ Jerre E. Birdsong
Name:		Jerre E. Birdsong
Title:		Vice President and Treasurer

Date: October 23, 2008

Exhibit Index

Exhibit No.		Description

**4.1		Indenture dated as of June 1, 2006, between IP and The Bank of New York Mellon Trust Company, N.A., as trustee, relating to the Notes (Annual Report on Form 10-K for the year ended December 31, 2007, Exhibit 4.101).

*4.2		Company Order establishing the Notes, including forms of global and definitive notes.

**4.3		General Mortgage Indenture and Deed of Trust dated as of November 1, 1992 between IP and The Bank of New York Mellon Trust Company, N.A. (formerly BNY Midwest Trust Company, successor to Harris Trust and Savings Bank), as trustee (Annual Report on Form 10-K for the year ended December 31, 2007, Exhibit 4.88).

*4.4		Supplemental Indenture dated as of October 1, 2008 by and between IP and The Bank of New York Mellon Trust Company, N.A. (formerly BNY Midwest Trust Company), as trustee, relating to the Mortgage Bonds, Senior Notes Series DD securing the Notes.

*99.1		Press release of IP dated October 21, 2008.

* Filed herewith.

** Incorporated by reference herein as indicated.

Exhibit 4.2

Company Order

October 23, 2008

The Bank of New York Mellon Trust Company, N.A.

Two North LaSalle Street, Suite 1020

Chicago, IL 60602

Ladies and Gentlemen:

Application is hereby made to The Bank of New York Mellon Trust Company, N.A., a national banking association, as trustee (the “Trustee”), under the Indenture dated as of June 1, 2006 (the “Indenture”), between Illinois Power Company, an Illinois corporation (the “Company”), and the Trustee for the authentication and delivery of $400,000,000 aggregate principal amount of the Company’s 9.75% Senior Secured Notes due 2018 (the “Notes”), pursuant to the provisions of Article II of the Indenture. Additional Notes without limitation as to amount, and without the consent of the holders of the then Outstanding Notes, may also be authenticated and delivered in the manner provided in Section 2.05 of the Indenture. All capitalized terms not defined herein that are defined in the Indenture shall have the same meaning as used in the Indenture.

The Notes will be initially issued pursuant to Section 4(2) of the Securities Act of 1933, as amended (the “Securities Act”), in the form of Global Notes registered in the name of Cede & Co. (as nominee for The Depository Trust Company (“DTC”), New York, New York, which will act as the Depositary for the Global Notes). Pursuant to Section 2.05(c) of the Indenture, the Notes will have the terms set forth in the form of Global Note attached hereto as Exhibit A and in the form of definitive Note attached hereto as Exhibit B (which terms are incorporated by reference in this Company Order). The Global Notes shall bear the depository legend in substantially the form set forth in Exhibit A attached hereto. The Notes will be issued only in denominations of $2,000 and in integral multiples of $1,000 in excess thereof.

Initially, beneficial interests in the Notes offered and sold to qualified institutional buyers (as defined in Rule 144A under the Securities Act) (“QIBs”) in reliance upon Rule 144A under the Securities Act will be represented by one or more separate Global Notes (each, a “Rule 144A Global Certificate”) registered in the name of Cede & Co., as registered owner and as nominee for DTC and shall include the non-registration and registration rights legends set forth in Exhibit A attached hereto. Initially beneficial interests in the Notes offered and sold to purchasers pursuant to Regulation S under the Securities Act will be evidenced by one or more separate Global Notes (each, a “Regulation S Global Certificate”) and will be registered in the name of Cede & Co., as registered owner and as nominee for DTC for the accounts of The Euroclear System (“Euroclear”) or Clearstream Banking, Luxembourg, société anonyme (“Clearstream”) and shall include the Regulation S and registration rights legends set forth in Exhibit A attached hereto. Notes offered and sold to institutional “accredited investors” (as defined in Rule 501(a)(1), (2), (3) or (7) under the Securities Act) who are not QIBs and who are not purchasers pursuant to Regulation S under the Securities Act will be in definitive form in the

form attached hereto as Exhibit B and shall include the non-registration and registration rights legends set forth therein. The Trustee and the Company will have no responsibility or liability for any aspect of transfers of beneficial interests in the Notes (which transfers will be conducted pursuant to the customary procedures of DTC), any records of DTC of beneficial interests or any transactions between DTC and its participants or between any such participants and any other beneficial owners or for monitoring, supervising or reviewing of any thereof.

Transfers of beneficial interests in the Rule 144A Global Certificate will be subject to the restrictions on transfer contained in the non-registration legend set forth in Exhibit A hereto. Prior to the expiration of the period of 40 consecutive days beginning on and including the later of (x) the day on which the offering of the Notes commences and (y) the original issue date of the Notes (the “Distribution Compliance Period”), transfers of beneficial interests in the Regulation S Global Certificate will be subject to the restrictions on transfer contained in the Regulation S legend set forth in Exhibit A hereto. After the expiration of the Distribution Compliance Period, transfers of beneficial interests in the Regulation S Global Certificate will not be subject to any restrictions.

In connection with any transfer of Notes, the Trustee and the Company shall be under no duty to inquire into, may conclusively presume the correctness of, and shall be fully protected in relying upon the certificates and other information (set forth in the form of definitive Note attached hereto as Exhibit B, for use in connection with the transfer of the Notes in definitive form, or set forth in Exhibit A-1 attached hereto, for use in connection with the transfer of beneficial interests between a Rule 144A Global Certificate and a Regulation S Global Certificate or to a Note in definitive form, or otherwise) received from the Holders and any transferees of any Notes regarding the validity, legality and due authorization of any such transfer, the eligibility of the transferee to receive such Note and any other facts and circumstances related to such transfer. Transfers of beneficial interests between a Rule 144A Global Certificate and a Regulation S Global Certificate, and other transfers relating to beneficial interests in the Notes in global form, shall be reflected by endorsements of the Trustee, as custodian for DTC, on the schedule attached to such certificate.

The Company has entered into a Registration Rights Agreement dated as of October 23, 2008 (the “Registration Rights Agreement”) with the initial purchasers of the Notes pursuant to which the Notes that are issued and sold without registration (the “Private Notes”) under the Securities Act may be exchanged for Notes that will be registered under the Securities Act and that will otherwise have substantially the same terms as the Private Notes (the “Exchange Notes”), except that such Exchange Notes will be issued in the form of Global Note attached hereto as Exhibit A and will bear all customary legends (except for the non-registration, Regulation S and registration rights legends) or, in lieu of such exchange, the Company has agreed to file a shelf registration statement for the resale of the Notes (in which case any Notes so resold will be issued in the form of Global Note attached hereto as Exhibit A and bear all customary legends (except for the non-registration, Regulation S and registration rights legends)). The Private Notes will be exchanged for Exchange Notes only pursuant to an effective registration statement under the Securities Act and otherwise in accordance with the Registration Rights Agreement and the Indenture. The Private Notes and the Exchange Notes will constitute a single series of notes under the Indenture. Exchange Notes shall be

authenticated and delivered by the Trustee at one time or from time to time upon the receipt by the Trustee of a Company Order in principal amounts equal to the principal amounts of the Private Notes surrendered in exchange therefor. In addition, upon the receipt of such Company Order, the Trustee will take such actions as to effectuate the exchange of any Private Notes for Exchange Notes in accordance with the Registration Rights Agreement and the Indenture.

In connection with this Company Order, there are delivered to you herewith the following:

1.		Certified copies of the resolutions adopted by the Board of Directors of the Company authorizing this Company Order and the issuance and sale of the Notes by the Company pursuant to Section 2.05(c)(1) of the Indenture;

2.		Opinions of Counsel addressed to you or in which it is stated that you may rely pursuant to Section 2.05(c)(2) of the Indenture;

3.		Expert’s certificate pursuant to Section 2.05(c)(3) of the Indenture;

4.		Officers’ Certificate pursuant to Section 2.05(c)(4) of the Indenture;

5.		Two Global Notes representing the Notes executed on behalf of the Company in accordance with the terms of Section 2.05(a) of the Indenture, specifying the terms of the Notes (which terms are incorporated by reference herein); and

6.		Pursuant to Section 2.05(c)(3) of the Indenture, the Company’s Mortgage Bonds designated “Mortgage Bonds, Senior Notes Series DD” (the “Mortgage Bonds”) in the principal amount of $400,000,000 relating to the Notes, fully registered in the name of the Trustee in trust for the benefit of the Holders from time to time of such Notes.

You are hereby instructed to authenticate the Global Notes representing the Notes and hold them as DTC’s custodian. The Global Notes representing the Notes are to be held for delivery through the facilities of DTC to the initial purchasers thereof against payment therefor at the closing in respect of the sale thereof, such closing to be held at 10:00 a.m., New York time, October 23, 2008, at the offices of Pillsbury Winthrop Shaw Pittman LLP, 1540 Broadway, New York, New York 10036.

Please acknowledge receipt of the Global Notes representing the Notes, the instructions referred to above and the supporting documentation pursuant to the Indenture referred to above (including the Mortgage Bonds in trust for the benefit of the Holders).

Very truly yours,

Illinois Power Company


By:	/s/ Jerre E. Birdsong
	Name:	Jerre E. Birdsong
	Title:	Vice President and Treasurer

Receipt from the Company of the Global Notes representing the Notes, certain instructions related thereto and the supporting documentation pursuant to the Indenture (including the Mortgage Bonds in trust for the benefit of the Holders) in connection with the authentication and delivery of the Notes is hereby acknowledged.

	The Bank of New York Mellon Trust Company, N.A.,
	as Trustee


	By:	/s/ Linda E. Garcia
		Name: Linda E. Garcia
		Title: Vice President

EXHIBIT A

FORM OF GLOBAL NOTE

[depository legend]

THIS SECURITY IS A GLOBAL NOTE REGISTERED IN THE NAME OF THE DEPOSITARY (REFERRED TO HEREIN) OR A NOMINEE THEREOF AND, UNLESS AND UNTIL IT IS EXCHANGED IN WHOLE FOR THE INDIVIDUAL NOTES REPRESENTED HEREBY AS PROVIDED IN THE INDENTURE REFERRED TO BELOW, THIS SECURITY MAY NOT BE TRANSFERRED EXCEPT AS A WHOLE BY THE DEPOSITARY TO A NOMINEE OF THE DEPOSITARY OR BY A NOMINEE OF THE DEPOSITARY TO THE DEPOSITARY OR ANOTHER NOMINEE OF THE DEPOSITARY OR BY THE DEPOSITARY OR ANY SUCH NOMINEE TO A SUCCESSOR DEPOSITARY OR A NOMINEE OF SUCH SUCCESSOR DEPOSITARY. UNLESS THIS SECURITY IS PRESENTED BY AN AUTHORIZED REPRESENTATIVE OF THE DEPOSITORY TRUST COMPANY (55 WATER STREET, NEW YORK, NEW YORK), TO THE TRUSTEE FOR REGISTRATION OF TRANSFER, EXCHANGE OR PAYMENT, AND ANY CERTIFICATE ISSUED IS REGISTERED IN THE NAME OF CEDE & CO. OR SUCH OTHER NAME AS REQUESTED BY AN AUTHORIZED REPRESENTATIVE OF THE DEPOSITORY TRUST COMPANY AND ANY PAYMENT IS MADE TO CEDE & CO., ANY TRANSFER, PLEDGE OR OTHER USE HEREOF FOR VALUE OR OTHERWISE BY OR TO ANY PERSON IS WRONGFUL SINCE THE REGISTERED OWNER HEREOF, CEDE & CO., HAS AN INTEREST HEREIN.

[non-registration legend to be included on Private Notes]

A-1

TRANSFER IS BEING MADE IN RELIANCE ON RULE 144A (AS INDICATED BY THE BOX CHECKED BY THE TRANSFEROR ON THE CERTIFICATE OF TRANSFER ATTACHED TO THIS SECURITY), (4) IN AN OFFSHORE TRANSACTION IN ACCORDANCE WITH RULE 903 OR 904 OF REGULATION S UNDER THE SECURITIES ACT (AS INDICATED BY THE BOX CHECKED BY THE TRANSFEROR ON THE CERTIFICATE OF TRANSFER ATTACHED TO THIS SECURITY), (5) TO AN INSTITUTION THAT IS AN “ACCREDITED INVESTOR” AS DEFINED IN RULE 501(a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

[Regulation S legend to be included on Private Notes]

BY ITS ACQUISITION HEREOF, EACH HOLDER OF THIS SECURITY, AND EACH PERSON THAT ACQUIRES A BENEFICIAL INTEREST IN SUCH SECURITY, AGREES THAT PRIOR TO THE EXPIRATION OF THE DISTRIBUTION COMPLIANCE PERIOD (AS DEFINED IN THE COMPANY ORDER ESTABLISHING THE TERMS OF THIS SECURITY), BENEFICIAL INTERESTS IN THIS SECURITY MAY ONLY BE OFFERED, RESOLD OR OTHERWISE TRANSFERRED (A) INSIDE THE UNITED STATES TO A QUALIFIED INSTITUTIONAL BUYER IN COMPLIANCE WITH RULE 144A UNDER THE SECURITIES ACT OF 1933 OR (B) OUTSIDE THE UNITED STATES IN COMPLIANCE WITH RULE 903 OR 904 UNDER THE SECURITIES ACT OF 1933 AND, IN EACH CASE, IN ACCORDANCE WITH ANY APPLICABLE SECURITIES LAWS OF THE STATES OF THE UNITED STATES OR ANY OTHER APPLICABLE JURISDICTION.

[registration rights legend to be included on Private Notes]

BY ITS ACCEPTANCE OF THE SECURITIES EVIDENCED HEREBY OR A BENEFICIAL INTEREST IN SUCH SECURITIES, THE HOLDER OF, AND ANY PERSON

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THAT ACQUIRES A BENEFICIAL INTEREST IN, SUCH SECURITIES AGREES TO BE BOUND BY THE PROVISIONS OF THE REGISTRATION RIGHTS AGREEMENT (THE “REGISTRATION RIGHTS AGREEMENT”) DATED AS OF OCTOBER 23, 2008 AND RELATING TO THE REGISTRATION UNDER THE SECURITIES ACT OF SECURITIES EXCHANGEABLE FOR THE SECURITIES EVIDENCED HEREBY AND REGISTRATION OF THE SECURITIES EVIDENCED HEREBY.

Illinois Commerce Commission ID No.: 6505

ILLINOIS POWER COMPANY

9.75% SENIOR SECURED NOTE DUE 2018

CUSIP: [452092CW7][U4504NCE7]	NUMBER: 1
ISIN: [US452092CW77][USU4504NCE77]

ORIGINAL ISSUE DATE: October 23, 2008	PRINCIPAL AMOUNT:	Listed on Schedule I hereto

INTEREST RATE: 9.75%	MATURITY DATE: November 15, 2018

ILLINOIS POWER COMPANY, a corporation of the State of Illinois (the “COMPANY”), for value received hereby promises to pay to CEDE & CO. or registered assigns, the principal amount specified above on the Maturity Date set forth above, and to pay interest thereon from and including the Original Issue Date specified above or from and including the most recent Interest Payment Date to which interest has been paid or duly provided for, semi-annually in arrears on May 15 and November 15 in each year, commencing May 15, 2009, and on the Maturity Date, at the per annum interest rate set forth above until the principal hereof is paid or made available for payment. If the Company does not comply with certain of its obligations under the Registration Rights Agreement, dated as of October 23, 2008, this bond shall, in accordance with Section 2(e) of such Registration Rights Agreement, bear additional interest (“Additional Interest”) in addition to the interest provided for in the immediately preceding sentence. For purposes of this Note, the term “interest” shall be deemed to include interest provided for in the second immediately preceding sentence and Additional Interest, if any. No interest shall accrue on the Maturity Date, so long as the principal amount of this Note is paid in full on the Maturity Date. The interest so payable and punctually paid or duly provided for on any such Interest Payment Date will (except for interest payable on the Maturity Date set forth above or, if applicable, upon redemption or acceleration), as provided in the Indenture (as defined below), be paid to the Person in whose name this Note is registered at the close of business on the Regular Record Date for such interest, which shall be May 1 or November 1, as the case may be, next preceding such Interest Payment Date; provided, that the first Interest Payment Date for any part of this Note, the Original Issue Date of which is after a Regular Record Date but prior to the applicable Interest Payment Date, shall be the Interest Payment Date following the next succeeding Regular Record Date; and provided, that interest payable on the Maturity Date set forth above or, if applicable, upon redemption or acceleration, shall be payable to the Person to whom principal shall be payable. Except as otherwise provided in the Indenture, any such interest not so punctually paid or duly provided for will forthwith cease to be payable to the Holder on such Regular Record Date and shall be paid to the Person in whose name this Note

A-3

is registered at the close of business on a Special Record Date for the payment of such defaulted interest to be fixed by the Trustee, notice whereof shall be given to Noteholders not more than fifteen days nor fewer than ten days prior to such Special Record Date. Payment of the principal of and interest and premium on this Note shall be payable pursuant to Section 2.12(a) of the Indenture.

This Note is a Global Note in respect of a duly authorized issue of 9.75% Senior Secured Notes due 2018 (the “NOTES OF THIS SERIES”, which term includes any Global Notes representing such Notes) of the Company issued and to be issued under an Indenture dated as of June 1, 2006 between the Company and The Bank of New York Mellon Trust Company, N.A., as trustee (herein called the “TRUSTEE”, which term includes any successor Trustee under the Indenture) and indentures supplemental thereto (collectively, the “INDENTURE”). Under the Indenture, one or more series of notes may be issued and, as used herein, the term “Notes” refers to the Notes of this Series. Reference is hereby made to the Indenture for a more complete statement of the respective rights, limitations of rights, duties and immunities thereunder of the Company, the Trustee and the Noteholders and of the terms upon which the Notes are and are to be authenticated and delivered. This Note has been issued in respect of the series designated on the first page hereof, issued in the initial aggregate principal amount of $400,000,000.

The Notes will be secured by mortgage bonds (the “SENIOR NOTE MORTGAGE BONDS”) delivered by the Company to the Trustee for the benefit of the Holders of the Notes, issued under the General Mortgage Indenture and Deed of Trust, dated as of November 1, 1992 between the Company and The Bank of New York Mellon Trust Company, N.A. (formerly BNY Midwest Trust Company), as successor trustee (the “MORTGAGE TRUSTEE”), as supplemented and modified (collectively, the “MORTGAGE”). Reference is made to the Mortgage and the Indenture for a description of the rights of the Trustee as holder of the Senior Note Mortgage Bonds, the property mortgaged and pledged, the nature and extent of the security and the rights of the holders of mortgage bonds, under the Mortgage and the rights of the Company and of the Mortgage Trustee in respect thereof, the duties and immunities of the Mortgage Trustee and the terms and conditions upon which the Senior Note Mortgage Bonds are secured and the circumstances under which additional mortgage bonds may be issued.

So long as any of the Notes of this Series are outstanding, the Company will not optionally redeem, purchase or otherwise retire in full its outstanding Mortgage Bonds, and, therefore, the Release Date will not occur.

Each Note of this Series shall be dated and issued as of the date of its authentication by the Trustee and shall bear an Original Issue Date. Each Note of this Series issued upon transfer, exchange or substitution of such Note shall bear the Original Issue Date of such transferred, exchanged or substituted Note, as the case may be.

Interest on this Note will accrue from and including the Original Issue Date specified above to, but excluding, May 15, 2009, and thereafter, from and including each Interest Payment Date to, but excluding, the next succeeding Interest Payment Date or the Maturity Date, as the case may be.

A-4

Interest payments for this Note shall be computed on the basis of a 360-day year consisting of twelve 30-day months. If any Interest Payment Date falls on a day that is not a Business Day, the Interest Payment Date will be the next succeeding Business Day (and without any interest or other payment in respect of any such delay). If the Maturity Date of this Note or any redemption date falls on a day that is not a Business Day, the payment of principal, premium, if any, and interest will be made on the next succeeding Business Day, and no interest on such payment shall accrue for the period from and after the Maturity Date or such redemption date.

All or a portion of the Notes of this Series may be redeemed at the option of the Company at any time or from time to time. The redemption price for the Notes of this Series to be redeemed on any redemption date will be equal to the greater of the following amounts: (a) 100% of the principal amount of the Notes of this Series being redeemed on the redemption date; or (b) the sum of the present values of the remaining scheduled payments of principal and interest on the Notes of this Series being redeemed on that redemption date (not including any portion of any payments of interest accrued to the redemption date) discounted to the redemption date on a semiannual basis at the Adjusted Treasury Rate (as defined below) plus 50 basis points, as determined by the Reference Treasury Dealer (as defined below); plus, in each case, accrued and unpaid interest thereon to the redemption date. Notwithstanding the foregoing, installments of interest on Notes of this Series that are due and payable on Interest Payment Dates falling on or prior to a redemption date will be payable on the Interest Payment Date to the Holder of this Note as of the close of business on the relevant Regular Record Date. The redemption price will be calculated on the basis of a 360-day year consisting of twelve 30-day months.

The Company shall mail notice of any redemption at least 30 days but not more than 60 days before the redemption date to each Holder of the Notes of this Series to be redeemed. Unless the Company defaults in payment of the redemption price, on and after the redemption date, interest will cease to accrue on the Notes of this Series or portions thereof called for redemption.

“ADJUSTED TREASURY RATE” means, with respect to any redemption date, the rate per annum equal to the semiannual equivalent yield to maturity of the Comparable Treasury Issue, assuming a price for the Comparable Treasury Issue (expressed as a percentage of its principal amount) equal to the Comparable Treasury Price for such redemption date.

“COMPARABLE TREASURY ISSUE” means the United States Treasury security selected by the Reference Treasury Dealer as having a maturity comparable to the remaining term of the Notes of this Series to be redeemed that would be utilized, at the time of selection and in accordance with customary financial practice, in pricing new issues of corporate debt securities of comparable maturity to the remaining term of such Notes of this Series.

“COMPARABLE TREASURY PRICE” means, with respect to any redemption date, (A) the average of the Reference Treasury Dealer Quotations for such redemption date, after excluding the highest and lowest of such Reference Treasury Dealer Quotations, or (B) if the Trustee obtains fewer than four such Reference Treasury Dealer Quotations, the average of all such quotations, or (C) if only one Reference Treasury Dealer Quotation is received, such quotation.

A-5

“REFERENCE TREASURY DEALER” means (A) Barclays Capital Inc., J.P. Morgan Securities Inc. or UBS Securities LLC or their respective affiliates which are primary U.S. Government securities dealers in the United States (each, a “Primary Treasury Dealer”), and their respective successors; provided, however, that if any of the foregoing shall cease to be a Primary Treasury Dealer, the Company shall substitute therefor another Primary Treasury Dealer; and (B) any other Primary Treasury Dealer(s) selected by the Company.

“REFERENCE TREASURY DEALER QUOTATIONS” means, with respect to each Reference Treasury Dealer and any redemption date, the average, as determined by the Company, of the bid and asked prices for the Comparable Treasury Issue (expressed in each case as a percentage of its principal amount) quoted in writing to the Company by such Reference Treasury Dealer at 5:00 p.m. (New York City time) on the third Business Day preceding such redemption date.

The Company, at its option, and subject to the terms and conditions provided in the Indenture, will be discharged from any and all obligations in respect of the Notes of this Series (except for certain obligations including obligations to register the transfer or exchange of Notes of this Series, replace stolen, lost or mutilated Notes of this Series, maintain paying agencies and hold monies for payment in trust, all as set forth in the Indenture) if the Company deposits with the Trustee money, U.S. Government Obligations which through the payment of interest thereon and principal thereof in accordance with their terms will provide money, or a combination of money and U.S. Government Obligations, in any event in an amount sufficient, without reinvestment, to pay all the principal of and any premium and interest on the Notes of this Series on the dates such payments are due in accordance with the terms of the Notes of this Series.

If an Event of Default shall occur and be continuing with respect to the Notes, the principal of and interest on the Notes may be declared due and payable in the manner and with the effect provided in the Indenture and, upon such declaration, the Trustee shall demand the redemption of the Senior Note Mortgage Bonds to the extent provided in the Indenture.

The Indenture permits, with certain exceptions as therein provided, the amendment thereof and the modifications of the rights and obligations of the Company and the rights of the Noteholders under the Indenture at any time by the Company and the Trustee with the consent of the Holders of a majority in aggregate principal amount of the outstanding Notes. Any such consent or waiver by the Holder of this Note shall be conclusive and binding upon such Holder and upon all future Holders of this Note and of any Note issued upon the registration of transfer hereof or in exchange therefor or in lieu thereof whether or not notation of such consent or waiver is made upon this Note.

As set forth in and subject to the provisions of the Indenture, no Holder of any Notes will have any right to institute any proceeding with respect to the Indenture or for any remedy thereunder unless such Holder shall have previously given to the Trustee written notice of a continuing Event of Default with respect to such Notes, the Holders of a majority in aggregate principal amount of the outstanding Notes affected by such Event of Default shall have made written request and offered reasonable indemnity to the Trustee to institute such proceeding as Trustee and the Trustee shall have failed to institute such proceeding within 60 days; provided, however, that such limitations do not apply to a suit instituted by the Holder hereof for the

A-6

enforcement of payment of the principal of and any premium or interest on this Note on or after the respective due dates expressed herein.

No reference herein to the Indenture and to provisions of this Note or of the Indenture shall alter or impair the obligation of the Company, which is absolute and unconditional, to pay the principal of and any premium and interest on this Note at the times, places and rates and the coin or currency prescribed in the Indenture.

As provided in the Indenture and subject to certain limitations therein set forth, this Note may be transferred only as permitted by the legend hereto and the provisions of the Indenture.

The Indenture and the Notes shall be governed by, and construed in accordance with, the laws of the State of New York without regard to conflicts of law principles thereof.

Unless the certificate of authentication hereon has been executed by the Trustee, directly or through an Authenticating Agent by manual signature of an authorized officer, this Note shall not be entitled to any benefit under the Indenture or be valid or obligatory for any purpose.

All terms used in this Note that are defined in the Indenture shall have the meanings assigned to them in the Indenture unless otherwise indicated herein.

A-7

IN WITNESS WHEREOF, the Company has caused this instrument to be duly executed.

		ILLINOIS POWER COMPANY


		By:

		Title:

		Attest:

		Title:

TRUSTEE’S CERTIFICATE
OF AUTHENTICATION

Dated: October 23, 2008

This Note is one of the Notes of the series herein
designated, described or provided for in the within-
mentioned Indenture.

THE BANK OF NEW YORK MELLON TRUST COMPANY, N.A., As Trustee

By:
	Authorized Signatory

A-8

SCHEDULE I

[144A]*[REGULATION S] * GLOBAL SECURITY

The initial principal amount of Notes evidenced by this Global Note is $ .

CHANGES TO PRINCIPAL AMOUNT OF NOTES EVIDENCED BY GLOBAL NOTE

Include bracketed language only in a Private Note.

A-9

EXHIBIT A-1

CERTIFICATE OF TRANSFER*

ILLINOIS POWER COMPANY

9.75% Senior Secured Notes due 2018

FOR VALUE RECEIVED, the undersigned sells, assigns and transfers unto

PLEASE INSERT SOCIAL SECURITY OR OTHER

IDENTIFYING NUMBER OF ASSIGNEE

Name and address of assignee must be printed or typewritten.

principal amount of beneficial interest in the referenced Security of the Company and does hereby irrevocably constitute and appoint

to transfer the said beneficial interest in such Security, with full power of substitution in the premises.

The undersigned certifies that said beneficial interest in said Security is being resold, pledged or otherwise transferred as follows:

(check one)

o		to the Company;

o		to a Person whom the undersigned reasonably believes is a qualified institutional buyer within the meaning of Rule 144A under the Securities Act of 1933, as amended (the “Securities Act”), purchasing for its own account or for the account of a qualified institutional buyer to whom notice is given that the resale, pledge or other transfer is being made in reliance on Rule 144A;

o		in an offshore transaction in accordance with Rule 903 or 904 of Regulation S under the Securities Act;

o		to an institution that is an “accredited investor” as defined in Rule 501(a)(1), (2), (3) or (7) under the Securities Act that is acquiring this Security for investment purposes and not for distribution (attach a copy of an Institutional Accredited Investor Certificate in the form annexed signed by an authorized officer of the transferee);

o		as otherwise permitted by the non-registration legend appearing on this Security; or

o		as otherwise agreed by the Company, confirmed in writing to the Trustee, as follows: [describe]

Dated:			Signature:

			NOTICE: The signature to this assignment must correspond with the name as written upon the face of the within instrument in every particular without alteration or enlargement, or any change whatever.

Include this form of Certificate of Transfer only in a Private Note.

A-10

SIGNATURE GUARANTEE

Signatures must be guaranteed by an “eligible guarantor institution” meeting the requirement of the registrar, which requirements include membership or participation in the Security Transfer Agent Medallion Program (“STAMP”) or such other “signature guarantee program” as may be determined by the registrar in addition to, or in substitution for, STAMP, all in accordance with the Securities Exchange Act of 1934, as amended.

A-11

[FORM OF INSTITUTIONAL ACCREDITED INVESTOR CERTIFICATE]*

[Transferor Name and Address]

Ladies and Gentlemen:

In connection with our proposed purchase of 9.75% Senior Secured Notes due 2018 (the “Notes”) issued by Illinois Power Company d/b/a AmerenIP (the “Issuer”), we confirm that:

1. We have received a copy of the Offering Memorandum (the “Offering Memorandum”) relating to the Notes and such other information as we deem necessary in order to make our investment decision. We acknowledge that we have read and agree to the matters stated under the caption NOTICE TO INVESTORS in such Offering Memorandum.

2. We understand that any subsequent transfer of the Notes is subject to certain restrictions and conditions set forth in the indenture relating to the Notes (the “Indenture”) and as set forth under NOTICE TO INVESTORS in the Offering Memorandum and the undersigned agrees to be bound by, and not to resell, pledge or otherwise transfer the Notes except in compliance with such restrictions and conditions and the Securities Act of 1933, as amended (the “Securities Act”).

3. We understand that the offer and sale of the Notes have not been registered under the Securities Act, and that the Notes may not be offered or sold except as permitted in the following sentence. We agree, on our own behalf and on behalf of any accounts for which we are acting as hereinafter stated, that if we sell any Notes, we will do so only (A) to the Issuer, (B) so long as the Notes are eligible for resale pursuant to Rule 144A under the Securities Act (“Rule 144A”), to a person whom we reasonably believe is a “qualified institutional buyer” within the meaning of Rule 144A that purchases for its own account or for the account of a qualified institutional buyer to whom notice is given that the resale, pledge or other transfer is being made in reliance on Rule 144A, (C) to an institutional “accredited investor” (as defined below) that, prior to such transfer, furnishes to the Trustee (as defined in the Indenture) a signed letter containing certain representations and agreements relating to the restrictions on transfer of the Notes (substantially in the form of this letter), (D) in an offshore transaction in accordance with Rule 904 of Regulation S under the Securities Act, (E) pursuant to the exemption from registration provided by Rule 144 under the Securities Act (if available), or (F) in accordance with another applicable exemption from the registration requirements of, or in a transaction not subject to, the Securities Act or pursuant to an effective registration statement under the Securities Act, and we further agree to provide to any person purchasing any of the Notes from us a notice advising such purchaser that resales of the Notes are restricted as stated herein.

Include this form only in a Private Note.

A-12

4. We understand that, on any proposed resale of any Notes, we will be required to furnish to the Trustee and the Issuer such certification and other information as the Trustee and the Issuer may reasonably require to confirm that the proposed sale complies with the foregoing restrictions. We further understand that the Notes purchased by us will bear a legend to the foregoing effect.

5. We are an institutional “accredited investor” (as defined in Rule 501(a)(1), (2), (3) or (7) under the Securities Act) and have such knowledge and experience in financial and business matters as to be capable of evaluating the merits and risks of our investment in the Notes, and we and any accounts for which we are acting are each able to bear the economic risk of our or its investment.

6. We are acquiring the Notes purchased by us for our own account or for one or more accounts (each of which is an institutional “accredited investor”) as to each of which we exercise sole investment discretion in each case for investment and not with a view to, or for offer or sale in connection with, any distribution in violation of the Securities Act.

You, the Issuer and the Trustee are entitled to rely upon this letter and are irrevocably authorized to produce this letter or a copy hereof to any interested party in any administrative or legal proceeding or official inquiry with respect to the matters covered hereby.

	Very truly yours,


	By:
		Name:
		Title:

A-13

EXHIBIT B

FORM OF DEFINITIVE NOTE

[non-registration legend to be included on Private Notes]

THIS SECURITY HAS NOT BEEN REGISTERED UNDER THE SECURITIES ACT OF 1933, AS AMENDED (THE “SECURITIES ACT”). THE HOLDER HEREOF, BY PURCHASING THIS SECURITY, AGREES FOR THE BENEFIT OF THE COMPANY THAT THIS SECURITY MAY NOT BE RESOLD, PLEDGED OR OTHERWISE TRANSFERRED PRIOR TO THE DATE WHICH IS ONE YEAR (OR SIX MONTHS IF ALL APPLICABLE CONDITIONS TO SUCH RESALE UNDER RULE 144 UNDER THE SECURITIES ACT (OR ANY SUCCESSOR PROVISION THEREOF) ARE SATISFIED) AFTER THE LATER OF THE ORIGINAL ISSUANCE DATE THEREOF, THE ISSUANCE DATE OF ANY SUBSEQUENT REOPENING AND THE LAST DATE ON WHICH THE COMPANY OR ANY AFFILIATE THEREOF WAS THE OWNER OF THIS SECURITY OR THE EXPIRATION OF SUCH SHORTER PERIOD AS MAY BE PRESCRIBED BY SUCH RULE 144 (OR SUCH SUCCESSOR PROVISION) PERMITTING RESALES OF THIS SECURITY WITHOUT ANY CONDITIONS (THE “RESALE RESTRICTION TERMINATION DATE”) OTHER THAN (1) TO THE COMPANY, (2) IN A TRANSACTION ENTITLED TO AN EXEMPTION FROM REGISTRATION PROVIDED BY RULE 144 UNDER THE SECURITIES ACT, (3) SO LONG AS THIS SECURITY IS ELIGIBLE FOR RESALE PURSUANT TO RULE 144A UNDER THE SECURITIES ACT (“RULE 144A”), TO A PERSON WHOM THE SELLER REASONABLY BELIEVES IS A QUALIFIED INSTITUTIONAL BUYER WITHIN THE MEANING OF RULE 144A PURCHASING FOR ITS OWN ACCOUNT OR FOR THE ACCOUNT OF A QUALIFIED INSTITUTIONAL BUYER TO WHOM NOTICE IS GIVEN THAT THE RESALE, PLEDGE OR OTHER TRANSFER IS BEING MADE IN RELIANCE ON RULE 144A (AS INDICATED BY THE BOX CHECKED BY THE TRANSFEROR ON THE CERTIFICATE OF TRANSFER ATTACHED TO THIS SECURITY), (4) IN AN OFFSHORE TRANSACTION IN ACCORDANCE WITH RULE 903 OR 904 OF REGULATION S UNDER THE SECURITIES ACT (AS INDICATED BY THE BOX CHECKED BY THE TRANSFEROR ON THE CERTIFICATE OF TRANSFER ON THE REVERSE OF THIS SECURITY), (5) TO AN INSTITUTION THAT IS AN “ACCREDITED INVESTOR” AS DEFINED IN RULE 501(a)(1), (2), (3) OR (7) UNDER THE SECURITIES ACT (AS INDICATED BY THE BOX CHECKED BY THE TRANSFEROR ON THE CERTIFICATE OF TRANSFER ON THE REVERSE OF THIS SECURITY) THAT IS ACQUIRING THIS SECURITY FOR INVESTMENT PURPOSES AND NOT FOR DISTRIBUTION, AND A CERTIFICATE IN THE FORM ATTACHED TO THIS SECURITY IS DELIVERED BY THE TRANSFEREE TO THE COMPANY AND THE TRUSTEE OR (6) IN ACCORDANCE WITH ANOTHER APPLICABLE EXEMPTION FROM, OR IN A TRANSACTION NOT SUBJECT TO, THE REGISTRATION REQUIREMENTS OF THE SECURITIES ACT OR PURSUANT TO AN EFFECTIVE REGISTRATION STATEMENT UNDER THE SECURITIES ACT, IN EACH CASE IN ACCORDANCE WITH ANY APPLICABLE SECURITIES LAWS OF ANY STATE OF THE UNITED STATES. AN INSTITUTIONAL ACCREDITED INVESTOR HOLDING THIS SECURITY AGREES IT WILL FURNISH TO THE COMPANY AND THE TRUSTEE SUCH CERTIFICATES AND OTHER INFORMATION AS THEY MAY REASONABLY REQUIRE TO CONFIRM THAT ANY TRANSFER BY IT OF THIS SECURITY COMPLIES

B-1

WITH THE FOREGOING RESTRICTIONS. THE FOREGOING RESTRICTIONS ON RESALE WILL NOT APPLY SUBSEQUENT TO THE RESALE RESTRICTION TERMINATION DATE. THE HOLDER OF THIS SECURITY ACKNOWLEDGES THAT THE COMPANY RESERVES THE RIGHT PRIOR TO ANY OFFER, SALE OR OTHER TRANSFER (1) PURSUANT TO CLAUSE (2) PRIOR TO THE RESALE RESTRICTION TERMINATION DATE TO REQUIRE THE DELIVERY OF AN OPINION OF COUNSEL, CERTIFICATIONS OR OTHER INFORMATION SATISFACTORY TO THE COMPANY AND (2) IN EACH OF THE FOREGOING CASES, TO REQUIRE THAT A CERTIFICATE AS TO COMPLIANCE WITH CERTAIN CONDITIONS TO TRANSFER IS COMPLETED AND DELIVERED BY THE TRANSFEROR TO THE COMPANY.

[Regulation S legend to be included on Private Notes]

[registration rights legend to be included on Private Notes]

BY ITS ACCEPTANCE OF THE SECURITIES EVIDENCED HEREBY OR A BENEFICIAL INTEREST IN SUCH SECURITIES, THE HOLDER OF, AND ANY PERSON THAT ACQUIRES A BENEFICIAL INTEREST IN, SUCH SECURITIES AGREES TO BE BOUND BY THE PROVISIONS OF THE REGISTRATION RIGHTS AGREEMENT (THE “REGISTRATION RIGHTS AGREEMENT”) DATED AS OF OCTOBER 23, 2008 AND RELATING TO THE REGISTRATION UNDER THE SECURITIES ACT OF SECURITIES EXCHANGEABLE FOR THE SECURITIES EVIDENCED HEREBY AND REGISTRATION OF THE SECURITIES EVIDENCED HEREBY.

B-2

Illinois Commerce Commission ID No.: 6505

ILLINOIS POWER COMPANY

9.75% SENIOR SECURED NOTE DUE 2018

CUSIP:						PRINCIPAL AMOUNT: $400,000,000
ISIN:

ORIGINAL ISSUE DATE: October 23, 2008						MATURITY DATE: November 15, 2018

INTEREST RATE: 9.75%						NUMBER: 1

ILLINOIS POWER COMPANY, a corporation of the State of Illinois (the “COMPANY”), for value received hereby promises to pay to CEDE & CO or registered assigns, the principal amount specified above on the Maturity Date set forth above, and to pay interest thereon from and including the Original Issue Date specified above or from and including the most recent Interest Payment Date to which interest has been paid or duly provided for, semi-annually in arrears on May 15 and November 15 in each year, commencing May 15, 2009, and on the Maturity Date, at the per annum interest rate set forth above until the principal hereof is paid or made available for payment. If the Company does not comply with certain of its obligations under the Registration Rights Agreement, dated as of October 23, 2008, this bond shall, in accordance with Section 2(e) of such Registration Rights Agreement, bear additional interest (“Additional Interest”) in addition to the interest provided for in the immediately preceding sentence. For purposes of this Note, the term “interest” shall be deemed to include interest provided for in the second immediately preceding sentence and Additional Interest, if any. No interest shall accrue on the Maturity Date, so long as the principal amount of this Note is paid in full on the Maturity Date. The interest so payable and punctually paid or duly provided for on any such Interest Payment Date will (except for interest payable on the Maturity Date set forth above or, if applicable, upon redemption or acceleration), as provided in the Indenture (as defined below), be paid to the Person in whose name this Note is registered at the close of business on the Regular Record Date for such interest, which shall be May 1 or November 1, as the case may be, next preceding such Interest Payment Date; provided, that the first Interest Payment Date for any part of this Note, the Original Issue Date of which is after a Regular Record Date but prior to the applicable Interest Payment Date, shall be the Interest Payment Date following the next succeeding Regular Record Date; and provided, that interest payable on the Maturity Date set forth above or, if applicable, upon redemption or acceleration, shall be payable to the Person to whom principal shall be payable. Except as otherwise provided in the Indenture (referred to on the reverse hereof), any such interest not so punctually paid or duly provided for will forthwith cease to be payable to the Holder on such Regular Record Date and shall be paid to the Person in whose name this Note is registered at the close of business on a Special Record Date for the payment of such defaulted interest to be fixed by the Trustee, notice whereof shall be given to Noteholders not more than fifteen days nor fewer than ten days prior to such Special Record Date. Principal, applicable premium and interest due at the Maturity of this Note shall be payable in immediately available funds when due upon presentation and surrender of this Note at the corporate trust office of the Trustee or at the authorized office of any paying agent in the Borough of Manhattan, The City and State of New York or Chicago, Illinois. Interest on this

B-3

Note (other than interest payable at Maturity) shall be paid by check payable in clearinghouse funds to the Holder as its name appears on the register; provided, that if the Trustee receives a written request from any Holder of Notes, the aggregate principal amount of all of which having the same Interest Payment Date as this Note equals or exceeds $10,000,000, on or before the applicable Regular Record Date for such Interest Payment Date, interest on the Note shall be paid by wire transfer of immediately available funds to a bank within the continental United States (designated by such Holder in its request or by direct deposit into the account of such Holder designated by such Holder in its request if such account is maintained with the Trustee or any paying agent).

REFERENCE IS HEREBY MADE TO THE FURTHER PROVISIONS OF THIS NOTE SET FORTH IN FULL ON THE REVERSE HEREOF, WHICH FURTHER PROVISIONS SHALL FOR ALL PURPOSES HAVE THE SAME EFFECT AS IF SET FORTH IN FULL AT THIS PLACE.

Unless the certificate of authentication hereon has been executed by the Trustee referred to on the reverse hereof, directly or through an Authenticating Agent by manual signature of an authorized officer, this Note shall not be entitled to any benefit under the Indenture or be valid or obligatory for any purpose.

B-4

IN WITNESS WHEREOF, the Company has caused this instrument to be duly executed.

	ILLINOIS POWER COMPANY

	By:

	Title:

	Attest:

	Title:

TRUSTEE’S CERTIFICATE
OF AUTHENTICATION

Dated: October 23, 2008

This Note is one of the Notes of the series herein

designated, described or provided for in the within-

mentioned Indenture.

THE BANK OF NEW YORK MELLON TRUST COMPANY, N.A., As Trustee

By:
	Authorized Signatory

B-5

[FORM OF REVERSE OF NOTE]

ILLINOIS POWER COMPANY
9.75% SENIOR SECURED NOTE DUE 2018

This Note is one of a duly authorized issue of 9.75% Senior Secured Notes due 2018 (the “NOTES OF THIS SERIES”) of the Company issued and to be issued under an Indenture dated as of June 1, 2006, between the Company and The Bank of New York Mellon Trust Company, N.A., as trustee (herein called the “TRUSTEE”, which term includes any successor Trustee under the Indenture) and indentures supplemental thereto (collectively, the “INDENTURE”). Under the Indenture, one or more series of notes may be issued and, as used herein, the term “Notes” refers to the Notes of this Series. Reference is hereby made to the Indenture for a more complete statement of the respective rights, limitations of rights, duties and immunities thereunder of the Company, the Trustee and the Noteholders and of the terms upon which the Notes are and are to be authenticated and delivered. This Note is one of the series designated on the face hereof, issued in the initial aggregate principal amount of $400,000,000.

B-6

any interest or other payment in respect of any such delay). If the Maturity Date of this Note or any redemption date falls on a day that is not a Business Day, the payment of principal, premium, if any, and interest will be made on the next succeeding Business Day, and no interest on such payment shall accrue for the period from and after the Maturity Date or such redemption date.

“REFERENCE TREASURY DEALER” means (A) Barclays Capital Inc., J.P. Morgan Securities Inc. or UBS Securities LLC or their respective affiliates which are primary U.S.

B-7

Government securities dealers in the United States (each, a “Primary Treasury Dealer”), and their respective successors; provided, however, that if any of the foregoing shall cease to be a Primary Treasury Dealer, the Company shall substitute therefor another Primary Treasury Dealer; and (B) any other Primary Treasury Dealer(s) selected by the Company.

B-8

As provided in the Indenture and subject to certain limitations therein set forth, the transfer of this Note is registrable in the Note register. Upon surrender of this Note for registration or transfer at the corporate trust office of the Trustee or such other office or agency as may be designated by the Company in the Borough of Manhattan, the City and State of New York, or Chicago, Illinois, endorsed by or accompanied by a written instrument of transfer in form satisfactory to the Company and the Note registrar, duly executed by the Holder hereof or the attorney in fact of such Holder duly authorized in writing, one or more new Notes of this Series of like tenor and of authorized denominations and for the same aggregate principal amount will be issued to the designated transferee or transferees.

The Notes of this Series are issuable only in registered form, without coupons, in denominations of $2,000 and integral multiples of $1,000 thereof. As provided in the Indenture and subject to certain limitations therein set forth, Notes of this Series are exchangeable for a like aggregate principal amount of Notes of this Series of like tenor and of a different authorized denomination, as requested by the Holder surrendering the same.

No service charge shall be made for any such registration of transfer or exchange but the Company may require payment of a sum sufficient to cover any tax or other governmental charge payable in connection therewith.

Prior to due presentment of this Note for registration of transfer, the Company, the Trustee and any agent of the Company or the Trustee may treat the Person in whose name this Note is registered as the owner thereof for all purposes, whether or not this Note is overdue, and neither the Company, the Trustee nor any such agent shall be affected by notice to the contrary.

The Indenture and the Notes shall be governed by, and construed in accordance with, the laws of the State of New York without regard to conflicts of law principles thereof.

All terms used in this Note that are defined in the Indenture shall have the meanings assigned to them in the Indenture unless otherwise indicated herein.

B-9

ABBREVIATIONS

The following abbreviations, when used in the inscription on the face of this instrument, shall be construed as though they were written out in full according to applicable laws or regulations:

TEN COM — as tenants in common	UNIF GIFT
	MIN ACT -		Custodian
		(Cust)		(Minor)
TEN ENT — as tenants by the
entireties	Under Uniform Gifts to Minors

JT TEN — as joint tenants with right
of survivorship and not as tenants in
common
	State

Additional abbreviations may also be used
though not in the above list.

B-10

CERTIFICATE OF TRANSFER*

ILLINOIS POWER COMPANY

9.75% Senior Secured Notes due 2018

FOR VALUE RECEIVED, the undersigned sells, assigns and transfers unto

PLEASE INSERT SOCIAL SECURITY OR OTHER

IDENTIFYING NUMBER OF ASSIGNEE

Name and address of assignee must be printed or typewritten.

principal amount of beneficial interest in the referenced Security of the Company and does hereby irrevocably constitute and appoint

to transfer the said beneficial interest in such Security, with full power of substitution in the premises.

The undersigned certifies that said beneficial interest in said Security is being resold, pledged or otherwise transferred as follows:

(check one)

o to the Company;

o to a Person whom the undersigned reasonably believes is a qualified institutional buyer within the meaning of Rule 144A under the Securities Act of 1933, as amended (the “Securities Act”), purchasing for its own account or for the account of a qualified institutional buyer to whom notice is given that the resale, pledge or other transfer is being made in reliance on Rule 144A;

o in an offshore transaction in accordance with Rule 903 or 904 of Regulation S under the Securities Act;

o to an institution that is an “accredited investor” as defined in Rule 501(a)(1), (2), (3) or (7) under the Securities Act that is acquiring this Security for investment purposes and not for distribution (attach a copy of an Institutional Accredited Investor Certificate in the form annexed signed by an authorized officer of the transferee);

o as otherwise permitted by the non-registration legend appearing on this Security; or

o as otherwise agreed by the Company, confirmed in writing to the Trustee, as follows: [describe]

Dated:				Signature:

				NOTICE: The signature to this assignment must correspond with the name as written upon the face of the within instrument in every particular without alteration or enlargement, or any change whatever.

* Include this form of Certificate of Transfer only in a Private Note.

B-11

SIGNATURE GUARANTEE

B-12

[FORM OF INSTITUTIONAL ACCREDITED INVESTOR CERTIFICATE]*

[Transferor Name and Address]

Ladies and Gentlemen:

In connection with our proposed purchase of 9.75% Senior Secured Notes due 2018 (the “Notes”) issued by Illinois Power Company d/b/a AmerenIP (the “Issuer”), we confirm that:

* Include this form only in a Private Note.

B-13

	Very truly yours,


	By:
		Name:
		Title:

B-14

Exhibit 4.4

WHEN RECORDED MAIL TO :
Illinois Power Company
Craig W. Stensland

One Ameren Plaza (MC 1310)
1901 Chouteau Avenue

St. Louis, MO 63103

ILLINOIS POWER COMPANY

THE BANK OF NEW YORK MELLON TRUST COMPANY, N.A.

(FORMERLY BNY MIDWEST TRUST COMPANY),

AS SUCCESSOR TRUSTEE TO

HARRIS TRUST AND SAVINGS BANK

SUPPLEMENTAL INDENTURE

DATED AS OF OCTOBER 1, 2008

GENERAL MORTGAGE INDENTURE AND DEED OF TRUST

DATED AS OF NOVEMBER 1, 1992

This instrument was prepared by Steven R. Sullivan, Senior Vice President, General Counsel and Secretary of Illinois Power Company c/o Ameren Corporation, One Ameren Plaza, 1901 Chouteau Avenue, St. Louis, Missouri 63103.

SUPPLEMENTAL INDENTURE dated as of October 1, 2008 (“Supplemental Indenture”), made by and between ILLINOIS POWER COMPANY, a corporation organized and existing under the laws of the State of Illinois (the “Company”), party of the first part, and THE BANK OF NEW YORK MELLON TRUST COMPANY, N.A. (formerly BNY Midwest Trust Company), a corporation organized and existing under the laws of the State of Illinois, as successor trustee to Harris Trust and Savings Bank, a corporation organized and existing under the laws of the State of Illinois (the “Trustee”), as Trustee under the General Mortgage Indenture and Deed of Trust dated as of November 1, 1992, hereinafter mentioned, party of the second part;

WHEREAS , the Company has heretofore executed and delivered its General Mortgage Indenture and Deed of Trust dated as of November 1, 1992 as from time to time amended (the “Indenture”), to the Trustee, for the security of the Bonds of the Company issued and to be issued thereunder (the “Bonds”); and

WHEREAS , pursuant to the terms and provisions of the Indenture there were created and authorized by supplemental indentures thereto bearing the following dates, respectively, the Mortgage Bonds of the series issued thereunder and respectively identified opposite such dates:

DATE OF SUPPLEMENTAL INDENTURE	IDENTIFICATION OF SERIES	CALLED

February 15, 1993	8% Series due 2023 (redeemed)	Bonds of the 2023 Series

March 15, 1993	6 1/8% Series due 2000 (paid at maturity)	Bonds of the 2000 Series

March 15, 1993	6 3/4% Series due 2005 (paid at maturity)	Bonds of the 2005 Series

July 15, 1993	7 1/2% Series due 2025 (redeemed)	Bonds of the 2025 Series

August 1, 1993	6 1/2% Series due 2003 (paid at maturity)	Bonds of the 2003 Series

October 15, 1993	5 5/8% Series due 2000 (paid at maturity)	Bonds of the Second 2000 Series

November 1, 1993	Pollution Control Series M (redeemed)	Bonds of the Pollution Control Series M

November 1, 1993	Pollution Control Series N (redeemed)	Bonds of the Pollution Control Series N

November 1, 1993	Pollution Control Series O (redeemed)	Bonds of the Pollution Control Series O

April 1, 1997	Pollution Control Series P	Bonds of the Pollution Control Series P

April 1, 1997	Pollution Control Series Q	Bonds of the Pollution Control Series Q

DATE OF SUPPLEMENTAL INDENTURE	IDENTIFICATION OF SERIES	CALLED

April 1, 1997	Pollution Control Series R	Bonds of the Pollution Control Series R

March 1, 1998	Pollution Control Series S	Bonds of the Pollution Control Series S

March 1, 1998	Pollution Control Series T	Bonds of the Pollution Control Series T

July 15, 1998	6 1/4% Series due 2002 (paid at maturity)	Bonds of the 2002 Series

September 15, 1998	6% Series due 2003 (paid at maturity)	Bonds of the Second 2003 Series

June 15, 1999	7.50% Series due 2009	Bonds of the 2009 Series

July 15, 1999	Pollution Control Series U	Bonds of the Pollution Control Series U

July 15, 1999	Pollution Control Series V (redeemed)	Bonds of the Pollution Control Series V

May 1, 2001	Pollution Control Series W	Bonds of the Pollution Control Series W

May 1, 2001	Pollution Control Series X	Bonds of the Pollution Control Series X

July 1, 2002	10 5/8% Series due 2007 (not issued)	Bonds of the 2007 Series

July 1, 2002	10 5/8% Series due 2012 (not issued)	Bonds of the 2012 Series

December 15, 2002	11.50% Series due 2010	Bonds of the 2010 Series

June 1, 2006	Mortgage Bonds, Senior Notes Series AA	Bonds of Series AA

August 1, 2006	Mortgage Bonds, 2006 Credit Agreement Series Bonds	2006 Credit Agreement Series Bonds

March 1, 2007	Mortgage Bonds, 2007 Credit Agreement Series Bonds	2007 Credit Agreement Series Bonds

November 15, 2007	Mortgage Bonds, Senior Notes Series BB	Bonds of Series BB

April 1, 2008	Mortgage Bonds, Senior Notes Series CC	Bonds of Series CC

and

WHEREAS , a supplemental indenture with respect to the Bonds of the 2007 Series and the Bonds of the 2012 Series listed above was executed and filed but such Bonds of the 2007

Series and Bonds of the 2012 Series were never issued and a release with respect to such supplemental indenture was subsequently executed and filed; and

WHEREAS , the Company desires to create a new series of Bonds to be issued under the Indenture to be known as “Mortgage Bonds, Senior Notes Series DD” (the “Series DD Mortgage Bonds”); and

WHEREAS , the Company has entered into an Indenture dated as of June 1, 2006 (the “Senior Note Indenture”) with The Bank of New York Mellon Trust Company, N.A., as trustee (the “Senior Note Trustee”), providing for the issuance from time to time of senior notes thereunder; and

WHEREAS , the Company desires by this Supplemental Indenture to issue to the Senior Note Trustee the Series DD Mortgage Bonds as security for $400,000,000 aggregate principal amount of the Company’s 9.75% Senior Secured Notes due 2018 (the “Senior Notes”) to be issued under the Senior Note Indenture; and

WHEREAS , the Company, in the exercise of the powers and authority conferred upon and reserved to it under the provisions of the Indenture, and pursuant to appropriate resolutions of the Board of Directors, has duly resolved and determined to make, execute and deliver to the Trustee this Supplemental Indenture in the form hereof for the purposes herein provided; and

WHEREAS , all conditions and requirements necessary to make this Supplemental Indenture a valid, binding and legal instrument have been done, performed and fulfilled and the execution and delivery hereof have been in all respects duly authorized;

NOW, THEREFORE, THIS SUPPLEMENTAL INDENTURE WITNESSETH:

THAT Illinois Power Company, in consideration of the purchase and ownership from time to time of the Bonds and the service by the Trustee, and its successors, under the Indenture and of One Dollar to it duly paid by the Trustee at or before the ensealing and delivery of these presents, the receipt whereof is hereby acknowledged, hereby covenants and agrees to and with the Trustee and its successors in the trust under the Indenture, for the benefit of those who shall hold the Bonds as follows:

The Series DD Mortgage Bonds shall be dated as provided in Section 3.03 of Article Three of the Indenture. The Series DD Mortgage Bonds shall mature on November 15, 2018,

shall accrue interest from the dates set forth in the Senior Notes and shall bear interest at the same rate of interest as the Senior Notes. Interest on the Series DD Mortgage Bonds is payable on the same dates as interest on the Senior Notes is paid, until the principal sum is paid in full.

Upon any payment of the principal of, premium, if any, and interest on, all or any portion of the Senior Notes, whether at maturity or prior to maturity by redemption or otherwise or upon provision for the payment thereof having been made in accordance with Section 5.01(a) of the Senior Note Indenture, the Series DD Mortgage Bonds in a principal amount equal to the principal amount of such Senior Notes shall, to the extent of such payment of principal, premium, if any, and interest, be deemed paid and the obligation of the Company thereunder to make such payment shall be discharged to such extent and, in the case of the payment of principal (and premium, if any), such Series DD Mortgage Bonds shall be surrendered to the Company for cancellation as provided in Section 4.08 of the Senior Note Indenture. The Trustee may at any time and all times conclusively assume that the obligation of the Company to make payments with respect to the principal of, premium, if any, and interest on the Senior Notes, so far as such payments at the time have become due, has been fully satisfied and discharged pursuant to the foregoing sentence unless and until the Trustee shall have received a written notice from the Senior Note Trustee signed by one of its officers stating (i) the timely payment of principal, or premium, if any, or interest on, the Senior Notes has not been made, (ii) that the Company is in arrears as to the payments required to be made by it to the Senior Note Trustee pursuant to the Senior Note Indenture, and (iii) the amount of the arrearage.

[FORM OF FACE OF BOND]

NOTWITHSTANDING ANY PROVISIONS HEREOF OR IN THE INDENTURE THIS BOND IS NOT ASSIGNABLE OR TRANSFERABLE EXCEPT AS PERMITTED BY SECTION 4.04 OF THE INDENTURE DATED AS OF JUNE 1, 2006, BETWEEN ILLINOIS POWER COMPANY AND THE BANK OF NEW YORK MELLON TRUST COMPANY, N.A., AS TRUSTEE

ILLINOIS POWER COMPANY

(Incorporated under the laws of the State of Illinois)

Illinois Commerce Commission
Identification No.: Ill. C.C. 6505

MORTGAGE BOND, SENIOR NOTES SERIES DD

No.

$400,000,000

ILLINOIS POWER COMPANY, a corporation organized and existing under the laws of the State of Illinois (the “Company”), which term shall include any successor corporation as defined in the Indenture hereinafter referred to, for value received, hereby promises to pay to The Bank of New York Mellon Trust Company, N.A., as trustee (the “Senior Note Trustee”) under the Indenture dated as of June 1, 2006 (the “Senior Note Indenture”), relating to the Company’s

9.75% Senior Secured Notes due 2018 (the “Senior Notes”) in the aggregate principal amount of $400,000,000, between the Company and the Senior Note Trustee, or registered assigns, the principal sum of $400,000,000 on November 15, 2018, in any coin or currency of the United States of America, which at the time of payment is legal tender for public and private debts, and to pay interest thereon in like coin or currency from the date of issuance (and thereafter from the dates set forth in the Senior Notes), and at the same rate of interest as the Senior Notes. Interest on overdue principal, premium, if any, and, to the extent permitted by law, on overdue interest, shall be payable at the interest rate payable on the Senior Notes. Interest on this Mortgage Bond is payable on the same dates as interest on the Senior Notes is paid, until the principal sum of this Mortgage Bond is paid in full. Pursuant to Article IV of the Senior Note Indenture, this Mortgage Bond is issued to the Senior Note Trustee to secure any and all obligations of the Company under the Senior Notes and any other series of senior notes from time to time outstanding under the Senior Note Indenture. Payment of principal of, or premium, if any, or interest on, the Senior Notes shall constitute payments on this Mortgage Bond as further provided herein and in the Supplemental Indenture of October 1, 2008 (as hereinafter defined) pursuant to which this Mortgage Bond has been issued. Both the principal of, premium, if any, and the interest on, this Mortgage Bond are payable at the office of the Senior Note Trustee.

Upon any payment of the principal of, premium, if any, and interest on, all or any portion of the Senior Notes, whether at maturity or prior to maturity by redemption or otherwise or upon provision for the payment thereof having been made in accordance with Section 5.01(a) of the Senior Note Indenture, a principal amount of this Mortgage Bond equal to the principal amount of such Senior Notes shall, to the extent of such payment of principal, premium, if any, and interest, be deemed paid and the obligation of the Company thereunder to make such payment shall be discharged to such extent and, in the case of the payment of principal (and premium, if any), such Mortgage Bonds shall be surrendered to the Company for cancellation as provided in Section 4.08 of the Senior Note Indenture. The Trustee (as hereinafter defined) may at any time and all times conclusively assume that the obligation of the Company to make payments with respect to the principal of, premium, if any, and interest on, the Senior Notes, so far as such payments at the time have become due, has been fully satisfied and discharged pursuant to the foregoing sentence unless and until the Trustee shall have received a written notice from the Senior Note Trustee signed by one of its officers stating (i) that timely payment of principal of, premium, if any, or interest on, the Senior Notes has not been made, (ii) that the Company is in arrears as to the payments required to be made by it to the Senior Note Trustee pursuant to the Senior Note Indenture, and (iii) the amount of the arrearage.

For purposes of Section 4.09 of the Senior Note Indenture, this Mortgage Bond shall be deemed to be the “Related Series of Senior Note Mortgage Bonds” in respect of the Senior Notes.

This Mortgage Bond shall not be entitled to any benefit under the Indenture or any indenture supplemental thereto, or become valid or obligatory for any purpose, until the form of certificate endorsed hereon shall have been signed by or on behalf of The Bank of New York Mellon Trust Company, N.A. (formerly BNY Midwest Trust Company), as successor trustee to Harris Trust and Savings Bank, the Trustee under the Indenture, or a successor trustee thereto under the Indenture (the “Trustee”).

The provisions of this Mortgage Bond are continued on the reverse hereof and such continued provisions shall for all purposes have the same effect as though fully set forth at this place.

IN WITNESS WHEREOF, Illinois Power Company has caused this Mortgage Bond to be signed (manually or by facsimile signature) in its name by an Authorized Executive Officer, as defined in the aforesaid Indenture, and attested (manually or by facsimile signature) by an Authorized Executive Officer, as defined in such Indenture on the date hereof.

Dated October 1, 2008

		ILLINOIS POWER COMPANY,

		By:
		AUTHORIZED EXECUTIVE OFFICER

ATTEST:

By:		AUTHORIZED EXECUTIVE OFFICER

[FORM OF TRUSTEE’S CERTIFICATE OF AUTHENTICATION]

This is one of the Mortgage Bonds of the series designated therein referred to in the within mentioned Indenture and the Supplemental Indenture dated as of October 1, 2008.

THE BANK OF NEW YORK MELLON TRUST COMPANY, N.A.

(formerly BNY Midwest Trust Company),

as successor trustee to

Harris Trust and Savings Bank,

TRUSTEE,

By:

AUTHORIZED SIGNATORY

[FORM OF REVERSE OF BOND]

This Mortgage Bond is one of a duly authorized issue of Mortgage Bonds of the Company (the “Mortgage Bonds”) in unlimited aggregate principal amount, of the series hereinafter specified, all issued and to be issued under and equally secured by the General Mortgage Indenture and Deed of Trust (the “Indenture”), dated as of November 1, 1992, executed by the Company to The Bank of New York Mellon Trust Company, N.A. (formerly BNY Midwest Trust Company), as successor trustee to Harris Trust and Savings Bank (the “Trustee”) to which Indenture and all indentures supplemental thereto reference is hereby made for a description of the properties mortgaged and pledged, the nature and extent of the security, the rights of registered owners of the Mortgage Bonds and of the Trustee in respect thereof, and the terms and conditions upon which the Mortgage Bonds are, and are to be, secured. The Mortgage Bonds may be issued in series, for various principal sums, may mature at different times, may bear interest at different rates and may otherwise vary as provided in the Indenture. This Mortgage Bond is one of a series designated as the Series DD Mortgage Bonds of the Company, unlimited in aggregate principal amount, issued under and secured by the Indenture and described in the Supplemental Indenture dated as of October 1, 2008 (the “Supplemental Indenture of October 1, 2008” ), between the Company and the Trustee, supplemental to the Indenture.

This Series DD Mortgage Bond is subject to redemption in accordance with the terms of Article II of the Supplemental Indenture of October 1, 2008.

In case an Event of Default, as defined in the Indenture, shall occur, the principal of all Mortgage Bonds at any such time outstanding under the Indenture may be declared or may become due and payable, upon the conditions and in the manner and with the effect provided in the Indenture. The Indenture provides that such declaration may be rescinded under certain circumstances.

ARTICLE II

REDEMPTION.

Section 1. The Series DD Mortgage Bonds are not redeemable except on the date, in the principal amount and for the redemption price that correspond to the redemption date for, the principal amount to be redeemed of, and the redemption price for, the Senior Notes, and except as set forth in Section 2 of this Article II.

In the event that the Company redeems any Senior Notes prior to maturity in accordance with the provisions of the Senior Note Indenture, the Senior Note Trustee shall on the same date deliver to the Company the Series DD Mortgage Bonds in principal amount corresponding to the Senior Notes so redeemed, as provided in Section 4.08 of the Senior Note Indenture. The Company agrees to give the Trustee notice of any such redemption of the Senior Notes on or before the date fixed for any such redemption.

Section 2. Upon the occurrence of an Event of Default under the Senior Note Indenture (as defined therein) and the acceleration of the Senior Notes, the Series DD Mortgage Bonds shall be redeemable in whole upon receipt by the Trustee (with a copy to the Company) of a written demand (hereinafter called a “Redemption Demand”) from the Senior Note Trustee stating that there has occurred under the Senior Note Indenture both an Event of Default and a declaration of acceleration of payment of principal, accrued interest and premium, if any, on the Senior Notes specifying the last date to which interest on such Senior Notes has been paid (such date being hereinafter referred to as the “Initial Interest Accrual Date”) and demanding redemption of the Series DD Mortgage Bonds. The Company waives any right it may have to prior notice of such redemption under the Indenture. Upon surrender of the Series DD Mortgage Bonds by the Senior Note Trustee to the Trustee, the Series DD Mortgage Bonds shall be redeemed at a redemption price equal to the principal amount thereof plus accrued interest thereon from the Initial Interest Accrual Date to the redemption date; provided, however, that in the event of a rescission or annulment of acceleration of the Senior Notes pursuant to the last paragraph of Section 8.01(a) of the Senior Note Indenture, then any Redemption Demand shall thereby be deemed to be rescinded by the Senior Note Trustee although no such rescission or annulment shall extend to or affect any subsequent default or impair any right consequent thereon.

ARTICLE III

ISSUE OF THE SERIES DD MORTGAGE BONDS.

Section 1. The Company hereby exercises the right to obtain the authentication of $400,000,000 principal amount of additional Bonds pursuant to the terms of Section 4.04 of the Indenture, all of which shall be Series DD Mortgage Bonds. The principal amount of the Series DD Mortgage Bonds outstanding from time to time shall always be equal to the principal amount of the Senior Notes which are outstanding from time to time under the Senior Note Indenture and to the extent the Senior Note Trustee holds Series DD Mortgage Bonds in excess of such principal amount, such Series DD Mortgage Bonds shall be deemed cancelled and retired and no longer outstanding under the Indenture.

Section 2. Such Series DD Mortgage Bonds may be authenticated and delivered prior to the filing for recordation of this Supplemental Indenture.

Section 3. For purposes of Section 4.09 of the Senior Note Indenture, the Series DD Mortgage Bonds shall be deemed to be the “Related Series of Senior Notes Mortgage Bonds” in respect of the Senior Notes.

ARTICLE IV

The Trustee hereby accepts the trusts hereby declared and provided, and agrees to perform the same upon the terms and conditions in the Indenture set forth and upon the following terms and conditions:

The Trustee shall not be responsible in any manner whatsoever for or in respect of the validity or sufficiency of this Supplemental Indenture or the due execution hereof by the Company or for or in respect of the recitals contained herein, all of which recitals are made by the Company solely. In general, each and every term and condition contained in Article Eleven of the Indenture shall apply to this Supplemental Indenture with the same force and effect as if the same were herein set forth in full, with such omissions, variations and modifications thereof as may be appropriate to make the same conform to this Supplemental Indenture.

ARTICLE V

This Supplemental Indenture may be simultaneously executed in any number of counterparts, each of which when so executed shall be deemed to be an original; but such counterparts shall together constitute but one and the same instrument.

IN WITNESS WHEREOF, said Illinois Power Company has caused this Supplemental Indenture to be executed on its behalf by an Authorized Executive Officer as defined in the Indenture, and its corporate seal to be hereto affixed and said seal and this Supplemental Indenture to be attested by an Authorized Executive Officer as defined in the Indenture; and said The Bank of New York Mellon Trust Company, N.A. (formerly BNY Midwest Trust Company), as successor trustee to Harris Trust and Savings Bank, in evidence of its acceptance of the trust hereby created, has caused this Supplemental Indenture to be executed on its behalf by its President or one of its Vice Presidents and its corporate seal to be hereto affixed and said seal and this Supplemental Indenture to be attested by its Secretary or one of its Vice Presidents; all as of October 1, 2008.

ILLINOIS POWER COMPANY

(CORPORATE SEAL)


	By:	/s/ Jerre E. Birdsong
		Name:	Jerre E. Birdsong
		Title:	Vice President and Treasurer

ATTEST:

By:	/s/ Ronald S. Gieseke
	Name:	Ronald S. Gieseke
	Title:	Assistant Secretary

THE BANK OF NEW YORK MELLON TRUST COMPANY, N.A.

(formerly BNY Midwest Trust Company),

successor trustee to

Harris Trust and Savings Bank,

TRUSTEE,

(CORPORATE SEAL)

By:	/s/ Rebekah Foltz
	Name:	Rebekah Foltz
	Title:	Vice President

ATTEST:

By:	/s/ Daniel G. Dwyer
	Name:	Daniel G. Dwyer
	Title:	Vice President

STATE OF MISSOURI	)
		ss.
CITY OF ST. LOUIS	)

BE IT REMEMBERED, that on this 16th day of October, 2008, before me, the undersigned, a Notary Public within and for the City and State aforesaid, personally came Jerre E. Birdsong, Vice President and Treasurer and Ronald S. Gieseke, Assistant Secretary, of Illinois Power Company, a corporation duly organized, incorporated and existing under the laws of the State of Illinois, who are personally known to me to be such officers, and who are personally known to me to be the same persons who executed as such officers the within instrument of writing, and such persons duly acknowledged that they signed, sealed and delivered the said instrument as their free and voluntary act as such officers and as the free and voluntary act of said Illinois Power Company for the uses and purposes therein set forth.

IN WITNESS WHEREOF, I have hereunto subscribed my name and affixed my official seal on the day and year last above written.

	/s/ Debra K. Patterson
	NOTARY PUBLIC

My Commission Expires on October 31, 2008

(NOTARIAL SEAL)

STATE OF MISSOURI	)
		ss.
CITY OF ST. LOUIS	)

BE IT REMEMBERED, that on this 16th day of October, 2008, before me, the undersigned, a Notary Public within and for the County and State aforesaid, personally came Rebekah Foltz, Vice President and Daniel G. Dwyer, Vice President, of The Bank of New York Mellon Trust Company, N.A., a corporation duly organized, incorporated and existing under the laws of the State of Illinois, who are personally known to me to be the same persons who executed as such officers the within instrument of writing, and such persons duly acknowledged that they signed, sealed and delivered the said instrument as their free and voluntary act as such Vice President and Vice President, and as the free and voluntary act of said The Bank of New York Mellon Trust Company, N.A. for the uses and purposes therein set forth.

IN WITNESS WHEREOF, I have hereunto subscribed my name and affixed my official seal on the day and year last above written.

	/s/ Matthew A. Biere
	NOTARY PUBLIC, MISSOURI

My Commission Expires on January 18, 2009

(NOTARIAL SEAL)

Exhibit 99.1

One Ameren Plaza

1901 Chouteau
Avenue

St. Louis, MO 63103

*Contact:*

*Media*	*Analysts*	*Investors*
Susan Gallagher	Doug Fischer	Investor Services
(314) 554-2175	(314) 554-4859	invest@ameren.com
sgallagher@ameren.com	dfischer@ameren.com

FOR IMMEDIATE RELEASE

Ameren Corporation Announces AmerenIP Refinancing

ST. LOUIS, MO, Oct. 21, 2008 — Ameren Corporation (NYSE: AEE) announced the pricing on Oct. 20, 2008, of a private offering of $400 million of 9.75% senior secured notes due 2018 by its subsidiary Illinois Power Company, doing business as AmerenIP. The transaction is expected to close on Oct. 23, 2008. AmerenIP intends to use the net proceeds of this private offering of approximately $391 million to repay short-term debt.

The notes will be offered and sold only to qualified institutional buyers in accordance with Rule 144A and Regulation S under the Securities Act of 1933. When issued, the notes will not have been registered under the Securities Act of 1933 or state securities laws and may not be offered or sold in the United States absent registration or an applicable exemption from the registration requirements of the Securities Act and applicable state securities laws.

This press release does not constitute an offer to sell or the solicitation of an offer to buy the notes or any other securities and shall not constitute an offer, solicitation or sale in any jurisdiction in which, or to any person to whom, such an offer, solicitation or sale is unlawful. Any offers of the notes will be made only by means of a private offering memorandum.

AmerenIP is a subsidiary of St. Louis-based Ameren Corporation. Ameren companies serve 2.4 million electric customers and one million natural gas customers in a 64,000-square-mile area of Missouri and Illinois.

Principal Amount of
Notes by which this
Global Note is to be
Reduced or Increased,
and Reason for
Reduction or Increase

Remaining Principal
Amount of Notes
Represented by this
Global Note

Notation Made by