Ameren Combined 8-K dated March 14, 2007


    Exhibit
      4.2

     

    When
      recorded mail to:

     

    
      	
               

              James
                A. Tisckos

              Central
                Illinois Public Service Company 

              607
                East Adams Street 

              Springfield,
                IL 62739 

            	 


    

     

    
      	 
	
              Executed
                in 100 Counterparts, No. __.

               

            
	
              Supplemental
                Indenture

               

            
	
              dated
                as of March 1, 2007

               

            
	
              Central
                Illinois Public Service Company

               

            
	
              To

               

            
	
              U.S.
                Bank National Association

            
	
              and
                Richard Prokosch,

              as
                trustees

            
	 
	
              (Supplemental
                to the Indenture of Mortgage or Deed of Trust 

              dated
                October 1, 1941, executed by Central Illinois Public Service Company
                

              to
                Continental Illinois National Bank and Trust Company of
                Chicago

              and
                Edmond B. Stofft, as trustees)

              (Providing
                for First Mortgage Bonds, 2007 Credit Agreement Series) 

               

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

               

            


    

    


    
      
        
        

      

      
        
        

        
          

        

      

      
        
        

      

    

    This
      Supplemental Indenture, dated as of March 1, 2007, made and entered into by
      and
      between CENTRAL ILLINOIS PUBLIC SERVICE COMPANY, a corporation organized and
      existing under the laws of the State of Illinois (hereinafter commonly referred
      to as the “Company”),
      and
      U.S. BANK NATIONAL ASSOCIATION (formerly U.S. Bank Trust National Association,
      formerly First Trust National Association, formerly First Trust of Illinois,
      National Association, successor trustee to Bank of America Illinois, formerly
      Continental Bank, formerly Continental Bank, National Association and formerly
      Continental Illinois National Bank and Trust Company of Chicago), a national
      banking association having its office or place of business in the City of
      Chicago, Cook County, State of Illinois (hereinafter commonly referred to as
      the
“Trustee”),
      and
      Richard Prokosch (successor Co-Trustee), of the City of Oakdale, Washington
      County, State of Minnesota, as Trustees under the Indenture of Mortgage or
      Deed
      of Trust dated October 1, 1941, heretofore executed and delivered by the Company
      to Continental Illinois National Bank and Trust Company of Chicago and Edmond
      B.
      Stofft, as Trustees, as amended by the Supplemental Indentures dated,
      respectively, September 1, 1947, January 1, 1949, February 1, 1952, September
      1,
      1952, June 1, 1954, February 1, 1958, January 1, 1959, May 1, 1963, May 1,
      1964,
      June 1, 1965, May 1, 1967, April 1, 1970, April 1, 1971, September 1, 1971,
      May
      1, 1972, December 1, 1973, March 1, 1974, April 1, 1975, October 1, 1976,
      November 1, 1976, October 1, 1978, August 1, 1979, February 1, 1980, February
      1,
      1986, May 15, 1992, July 1, 1992, September 15, 1992, April 1, 1993, June 1,
      1995, March 15, 1997, June 1, 1997, December 1, 1998, June 1, 2001, October
      1,
      2004, June 1, 2006 and August 1, 2006 heretofore executed and delivered by
      the
      Company to the Trustees under said Indenture of Mortgage or Deed of Trust dated
      October 1, 1941; said Indenture of Mortgage or Deed of Trust dated October
      1,
      1941, as amended by said Supplemental Indentures, being hereinafter sometimes
      referred to as the “Indenture”;
      and
      said U.S. Bank National Association and Richard Prokosch (successor Co-Trustee),
      of the City of Oakdale, Washington County, State of Minnesota, as Trustees,
      as
      such Trustees, being hereinafter sometimes referred to as the “Trustees”
or
      the
“Trustees
      under the Indenture”;

     

    WITNESSETH:

     

    WHEREAS,
      the Company has entered into a Credit Agreement, dated as of February 9, 2007
      (as amended or otherwise modified from time to time, the “Credit
      Agreement”)
      by and
      among the Company, Central Illinois Light Company, Illinois Power Company,
      AmerenEnergy Resources Generating Company and CILCORP Inc., as borrowers, the
      lenders from time to time party thereto (the “Lenders”)
      and
      JPMorgan Chase Bank, N.A., as agent (in such capacity, the “Agent”)
      for
      the Lenders, providing for the making of certain financial accommodations
      thereunder to the Company, and pursuant to such Credit Agreement, the Company
      has agreed to issue to the Agent, as evidence of and security for the
      Obligations (as such term is defined in the Credit Agreement) of the Company
      (the “Company
      Obligations”),
      a new
      series of bonds under the Indenture;

     

    WHEREAS,
      for such purposes, the Company has determined, by resolutions duly adopted
      by
      its Board of Directors, to issue bonds of an additional series under and to
      be
      secured by the Indenture, as hereby amended, to be known and designated as
      First
      Mortgage Bonds, 2007 Credit Agreement Series (hereinafter sometimes referred
      to
      as the “bonds
      of 2007 Credit Agreement Series”
or
      the
“bonds
      of said Series”),
      and
      the bonds of said Series shall be authorized, authenticated and issued only
      as
      registered bonds without coupons, and to execute

     

    
      
        
        

      

      
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     and
      deliver this supplemental indenture, pursuant to the provisions of Article
      I, as
      amended, Section 6 of Article II and Article XVI of the Indenture, for the
      purpose of (1) creating and authorizing not to exceed $135,000,000 aggregate
      principal amount of bonds of 2007 Credit Agreement Series and setting forth
      the
      form, terms, provisions and characteristics thereof, and (2) modifying or
      amending certain provisions of the Indenture in the particulars and to the
      extent hereinafter specifically provided; and

     

    WHEREAS,
      the bonds of 2007 Credit Agreement Series shall
      be
      issued to the Agent as evidence of and security for the Company Obligations
      under the Credit Agreement;

     

    WHEREAS,
      the execution and delivery by the Company of this supplemental indenture have
      been duly authorized by the Board of Directors of the Company; and the Company
      has requested, and hereby requests, the Trustees to enter into and join with
      the
      Company in the execution and delivery of this supplemental indenture;
      and

     

    WHEREAS,
      the bonds of 2007 Credit Agreement Series are to be authorized, authenticated
      and issued only in the form of registered bonds without coupons, and the bonds
      of 2007 Credit Agreement Series and the certificate of the Trustee thereon
      shall
      be substantially in the following form, to wit:

     

    [FORM
      OF
      BOND]

     

    
      	
              No.
                _______

               

            	
              $__________

               

            


    

    Illinois
      Commerce Commission

    Identification
      No.: Ill. C.C. No. ____

     

    Notwithstanding
      any provisions hereof or in the Indenture

    this
      Bond is not assignable or transferable except to a successor Agent appointed
      in


    accordance
      with the Credit Agreement, dated 

    as
      of February 9, 2007, hereinafter referred to.

     

    Central
      Illinois Public Service Company

    First
      Mortgage Bond, 2007 Credit Agreement Series 

     

    
      	
              REGISTERED
                OWNER: JPMorgan Chase Bank, N.A., 

            
	
               

              PRINCIPAL
                AMOUNT _______________________________ 
                DOLLARS

            


    

    


     

    CENTRAL
      ILLINOIS PUBLIC SERVICE COMPANY, an Illinois corporation (hereinafter referred
      to as the “Company”),
      for
      value received, hereby promises to pay to the Registered Owner specified above,
      as agent (in such capacity, the “Agent”) for the Lenders (as defined below)
      under the Credit Agreement, dated as of February 9, 2007, by and among the
      Company, Central Illinois Light Company, Illinois Power Company, AmerenEnergy
      Resources Generating Company and CILCORP Inc., as borrowers, the lenders from
      time to time party thereto (the “Lenders”)
      and
      JPMorgan Chase Bank, N.A., as agent (as amended or otherwise modified from
      time
      to time, the “Credit
      Agreement”),
      or
      registered assigns, the Principal Amount 

     

    
      
        
        

      

      
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    specified
      above or such lesser principal amount as shall be equal to the Borrower Credit
      Exposure (as defined in the Credit Agreement) of the Company outstanding on
      the
      Maturity Date (having at any time the meaning such term has at such time under
      the Credit Agreement) of the Company, but not in excess of the Principal Amount
      of this bond, and to pay interest thereon at the Interest Rate (as defined
      below) until the principal hereof is paid or duly made available for payment
      on
      the Maturity Date or in the event of redemption of this bond, until the
      redemption date. 

     

    Interest
      on this bond shall be payable on each Interest Payment Date (as defined below),
      commencing on the first Interest Payment Date next succeeding the date of this
      bond. If the Maturity Date falls on a day which is not a Business Day, as
      defined below, principal and any interest and/or fees payable with respect
      to
      the Maturity Date will be paid on the next succeeding Business Day. The interest
      payable, and punctually paid or duly provided for, on any Interest Payment
      Date
      will, subject to certain exceptions provided in the Supplemental Indenture
      dated
      as of March 1, 2007, hereinafter referred to, be paid to the person in whose
      name this bond (or one or more predecessor bonds) is registered at the close
      of
      business on the Record Date (as defined below); provided, however, that interest
      payable on the Maturity Date will be payable to the person to whom the principal
      hereof shall be payable. Should the Company default in the payment of interest
      (“Defaulted Interest”), the Defaulted Interest shall be paid to the person in
      whose name this bond is registered on the Record Date to be established by
      the
      Trustee for payment of such Defaulted Interest. As used herein, (A) “Business
      Day” shall have the meaning assigned thereto in the Credit Agreement; (B)
“Interest Payment Date” shall mean each date on which Company Obligations
      constituting interest and/or fees are due and payable from time to time pursuant
      to the Credit Agreement; (C) “Interest Rate” shall mean a rate of interest per
      annum, adjusted as necessary, to result in an interest payment equal to the
      aggregate amount of Company Obligations constituting interest and fees of the
      Company due under the Credit Agreement on the applicable Interest Payment Date;
      and (D) “Record Date” with respect to any Interest Payment Date shall mean the
      day (whether or not a Business Day) immediately next preceding such Interest
      Payment Date.

     

    Both
      the
      principal of and the interest on this bond shall be payable in immediately
      available funds at the office or agency of the Trustee, 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. 

     

    This
      bond
      is one of the bonds issued and to be issued from time to time under and in
      accordance with and all secured by the indenture of mortgage or deed of trust
      dated October 1, 1941, executed and delivered by the Company to U.S. Bank
      National Association (formerly U.S. Bank Trust National Association, formerly
      First Trust National Association, formerly First Trust of Illinois, National
      Association, successor trustee to Bank of America Illinois, formerly Continental
      Bank, formerly Continental Bank, National Association and formerly Continental
      Illinois National Bank and Trust Company of Chicago and hereinafter referred
      to
      as the “Trustee”)
      and
      Edmond B. Stofft, as Trustees, and the various indentures supplemental thereto,
      including the Supplemental Indenture pursuant to which $135,000,000 in aggregate
      principal amount of the First Mortgage Bonds, 2007 Credit Agreement Series
      (the
“2007
      Credit Agreement Series Bonds”)
      are
      authorized, each executed and delivered by the Company to the Trustees under
      said indenture of mortgage or deed of trust dated October 1, 1941, prior to
      the
      authentication of this bond (said indenture of mortgage or deed of trust and
      said supplemental

     

    
      
        
        

      

      
        4

        
          

        

      

      
        
        

      

    

     

     indentures
      being hereinafter referred to, collectively, as the “Indenture”);
      and
      said U.S. Bank National Association and Richard Prokosch (successor Co-Trustee),
      of the City of Oakdale, Washington County, State of Minnesota, as Trustees
      (successor Co-Trustee) being now the Trustees under the Indenture. Reference
      to
      the Indenture and to all supplemental indentures, if any, hereafter executed
      pursuant to the Indenture is hereby made for a description of the property
      mortgaged and pledged, the nature and extent of the security and the rights
      of
      the holders and Registered Owners of said bonds and of the Trustees and of
      the
      Company in respect of such security. By the terms of the Indenture the bonds
      to
      be secured thereby are issuable in series, which may vary as to date, amount,
      date of maturity, rate of interest, redemption provisions, medium of payment
      and
      in other respects as in the Indenture provided. 

     

    The
      2007
      Credit Agreement Series Bonds are
      to be
      issued and delivered to the Agent in order to evidence and secure the
      obligations of the Company under the Credit Agreement to make payments to the
      Lenders under the Credit Agreement and to provide the Lenders the benefit of
      the
      lien of the Indenture with respect to the 2007 Credit Agreement Series
      Bonds.

     

    The
      obligation of the Company to make payments with respect to principal under
      the
      Credit Agreement shall not give rise to an obligation to pay principal of the
      2007 Credit Agreement Series Bonds except on the Maturity Date of the Company
      or
      upon redemption hereof. If at any time any permanent reduction of the Borrower
      Sublimit (as defined in the Credit Agreement) of the Company or the Borrower
      Credit Exposure (as defined in the Credit Agreement) of the Company shall result
      in the principal of the 2007 Credit Agreement Series Bonds being greater than
      the greater of the Borrower Sublimit and the Borrower Credit Exposure, a payment
      obligation with respect to the principal of the 2007 Credit Agreement Series
      Bonds in the amount of such excess shall be deemed discharged upon the
      effectiveness of such permanent reduction. No payment of principal under the
      Credit Agreement shall reduce the principal amount of the 2007
      Credit Agreement Series Bonds to an amount less than the greater of the Borrower
      Sublimit and the Borrower Credit Exposure.

     

    The
      obligation of the Company to make payments with respect to the interest on
      the
      2007 Credit
      Agreement Series Bonds shall be fully or partially, as the case may be,
      satisfied and discharged to the extent that, at the time that any such payment
      shall be due, the then due interest and/or fees of the Company under the Credit
      Agreement shall have been fully or partially paid. Satisfaction of any
      obligation to the extent that payment is made with respect to the interest
      and/or fees of the Company under the Credit Agreement means that if any payment
      is made on the interest and/or fees of the Company under the Credit Agreement,
      a
      corresponding payment obligation with respect to the interest on the 2007 Credit
      Agreement Series Bonds shall be deemed discharged in the same amount as such
      payment made on the interest and/or fees of the Company under the Credit
      Agreement.

     

    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 and interest
      on
      the 2007 Credit Agreement Series Bonds, so far as such payments at the time
      have
      become due, has been fully satisfied and discharged pursuant to the foregoing
      paragraphs unless and until the Trustee shall have received a written notice
      from the Agent stating (i) that timely payment of principal of or interest
      on
      the 2007 Credit Agreement Series Bonds has not been made, (ii) that the Company
      is 

     

     

    
      
        
        

      

      
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    in
      arrears as to the payments required to be made by it to the Agent in connection
      with the Company Obligations pursuant to the Credit Agreement, and (iii) the
      amount of the arrearage.

     

    This
      bond
      is not redeemable except upon written demand of the Agent following the
      occurrence of a Default by the Company under the Credit Agreement and the
      acceleration of the Company Obligations, as provided under the Credit Agreement.
      

     

    In
      case
      of certain events of default specified in the Indenture, the principal of this
      bond may be declared or may become due and payable in the manner and with the
      effect provided in the Indenture. No recourse shall be had for the payment
      of
      the principal of or interest on this bond, or for any claim based hereon, or
      otherwise in respect hereof or of the Indenture or any indenture supplemental
      thereto, to or against any incorporator, stockholder, officer or director,
      past,
      present or future, of the Company, or of any predecessor or successor
      corporation, either directly or through the Company, or such predecessor or
      successor corporation, under any constitution or statute or rule of law, or
      by
      the enforcement of any assessment, penalty, or otherwise, all such liability
      of
      incorporators, stockholders, directors and officers being waived and released
      by
      the Registered Owner hereof by the acceptance of this bond and being likewise
      waived and released by the terms of the Indenture.

     

    This
      bond
      shall not be assignable or transferable except to a successor Agent appointed
      in
      accordance with the Credit Agreement. This bond is exchangeable by the
      Registered Owner hereof, in person or by attorney duly authorized, at the
      principal office or place of business of the Trustee under the Indenture, upon
      the surrender and cancellation of this bond and the payment of any stamp tax
      or
      other governmental charge, and upon any such exchange a new registered bond
      or
      bonds without coupons, of the same series and maturity and for the same
      aggregate principal amount, will be issued in exchange heretofore; provided,
      that the Company shall not be required to exchange any bonds of 2007 Credit
      Agreement Series for a period of ten (10) days next preceding an Interest
      Payment Date with respect to such bonds.

     

    The
      Agent
      shall surrender this bond to the Trustee when each of the Borrower Sublimit
      and
      the Borrower Credit Exposure have been reduced to zero and all fees and other
      amounts payable by the Company pursuant to the Credit Agreement with respect
      to
      the Company Obligations shall have been duly paid.

     

    This
      bond
      shall not be valid or become obligatory for any purpose unless and until it
      shall have been authenticated by the execution by the Trustee or its successor
      in trust under the Indenture of the Trustee’s Certificate endorsed
      hereon.

     


    
      
        
        

      

      
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    IN
      WITNESS WHEREOF, Central Illinois Public Service Company has caused this bond
      to
      be executed in its name by the manual or facsimile signature of its President
      or
      one of its Vice-Presidents, and its corporate seal or a facsimile thereof to
      be
      affixed or imprinted hereon and attested by the manual or facsimile signature
      of
      its Secretary or one of its Assistant Secretaries.

     

    
      	
               

               

            	
              CENTRAL
                ILLINOIS PUBLIC SERVICE COMPANY

               

              By
                ______________________________

              President

            
	
              Attest:

               

              By_____________________________

              Secretary

            	 


    

     

    This
      bond
      is one of the bonds of the series designated therein, described in the within
      mentioned Indenture.

     

    
      	
               

            	
              U.S.
                BANK NATIONAL ASSOCIATION, as 

              Trustee

               

              By_______________________________

              Authorized
                Officer

            


    

     

    [END
      OF
      FORM OF BOND]

     

    


    NOW,
      THEREFORE, in consideration of the premises and of the sum of One Dollar ($1.00)
      duly paid by the Trustees to the Company, and of other good and valuable
      considerations, the receipt whereof is hereby acknowledged, and for the purpose
      of further securing the due and punctual payment of the principal of and
      interest on all bonds which have been heretofore or shall be hereafter issued
      under the Indenture and indentures supplemental thereto and which shall be
      at
      any time outstanding thereunder and secured thereby and $135,000,000 aggregate
      principal amount of the bonds of 2007 Credit Agreement Series, and for the
      purpose of securing the faithful performance and observance of all the covenants
      and conditions set forth in the Indenture and/or in any indenture supplemental
      thereto, the Company has given, granted, bargained, sold, transferred, assigned,
      pledged, mortgaged, warranted the title to and conveyed, and by these presents
      does give, grant, bargain, sell, transfer, assign, pledge, mortgage, warrant
      the
      title to and convey unto U.S. Bank National Association and Richard Prokosch
      (successor Co-Trustee), of the City of Oakdale, Washington County, State of
      Minnesota, as Trustees, as Trustees under the Indenture as therein provided,
      and
      their successors in the trusts thereby created, and to their assigns, all the
      right, title and interest of the Company 

     

     

    
      
        
        

      

      
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    in
      and to
      any and all premises, plants, property, leases and leaseholds, franchises,
      permits, rights and powers, of every kind and description, real and personal,
      which have been acquired by the Company through construction, purchase,
      consolidation or merger, or otherwise, subsequent to January 1, 2006, and which
      are owned by the Company at the date of the execution hereof, together with
      the
      rents, issues, products and profits therefrom, excepting, however, and there
      is
      hereby expressly reserved and excluded from the lien and effect of the Indenture
      and of this supplemental indenture, all right, title and interest of the
      Company, now owned, in and to (a) all cash, bonds, shares of stock, obligations
      and other securities not deposited with the Trustee or Trustees under the
      Indenture, and (b) all accounts and bills receivable, judgments (other than
      for
      the recovery of real property or establishing a lien or charge thereon or right
      therein) and chooses in action not specifically assigned to and pledged with
      the
      Trustee or Trustees under the Indenture, and (c) all personal property acquired
      or manufactured by the Company for sale, lease, rental or consumption in the
      ordinary course of business, and (d) the last day of each of the demised terms
      created by any lease of property leased to the Company and under each and every
      renewal of any such lease, the last day of each and every such demised term
      being hereby expressly reserved to and by the Company, and (e) all gas, oil
      and
      other minerals now or hereafter existing upon, within or under any real estate
      of the Company subject to, or hereby subjected to, the lien of the
      Indenture.

     

    And
      upon
      the considerations and for the purposes aforesaid, and in order to provide,
      pursuant to the terms of the Indenture, for the issuance under the Indenture,
      as
      hereby amended, of bonds of 2007 Credit Agreement Series and to fix the terms,
      provisions and characteristics of the bonds of 2007 Credit Agreement Series,
      and
      to modify or amend the Indenture in the particulars and to the extent
      hereinafter in this supplemental indenture specifically provided, the Company
      hereby covenants and agrees with the Trustees as follows:

     

    Article
      I   

     

    Section
      1.1  A
      series
      of bonds issuable under the Indenture, as hereby amended, to be known and
      designated as “First
      Mortgage Bonds, 2007 Credit Agreement Series”
and
      which shall be executed, authenticated and issued only in the form of registered
      bonds without coupons, is hereby created and authorized. The bonds of 2007
      Credit Agreement Series and the Trustee’s Certificate to be endorsed thereon
      shall be substantially in the form thereof hereinbefore recited (the
“Bond
      Form”).
      Each
      bond of 2007 Credit Agreement Series is to be issued and registered in the
      name
      of the Agent under the Credit Agreement to evidence and secure any and all
      Obligations (as such term is defined in the Credit Agreement) of the Company
      (the “Company
      Obligations”)
      under
      the Credit Agreement. Each bond of 2007 Credit Agreement Series shall be dated
      as of the Interest Payment Date (as defined below) thereof to which interest
      was
      paid next preceding the date of issue, unless (a) issued on an Interest Payment
      Date thereof to which interest was paid, in which event it shall be dated as
      of
      such issue date, or (b) issued prior to the occurrence of the first Interest
      Payment Date thereof to which interest was paid, in which event it shall be
      dated the date of original issuance. 

     

    The
      bonds
      of 2007 Credit Agreement Series shall be issued in the aggregate principal
      amount of not to exceed $135,000,000 and shall mature on the Maturity Date
      (having at any time the meaning such term has at such time under the Credit
      Agreement) of the Company. The principal amount of bonds of the 2007 Credit
      Agreement Series outstanding from time to time 

     

    
      
        
        

      

      
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    shall
      always be equal to the greater of (i) the Company’s Borrower Sublimit (as
      defined in the Credit Agreement, without giving effect to clause (ii) of such
      definition) and (ii) the Borrower Credit Exposure (as defined in the Credit
      Agreement) of the Company on the Maturity Date, but not in excess of
      $135,000,000. Under the Credit Agreement, the Company must at any time it
      increases its Borrower Sublimit deliver additional bonds of the 2007 Credit
      Agreement Series in an amount such that the requirement of the preceding
      sentence is at that time satisfied. Upon submission of the appropriate
      certificates and opinions as required under the Indenture, the Company may
      so
      issue and the Trustee shall authenticate from time to time bonds of the 2007
      Credit Agreement Series at any time on or prior to January 14,
      2010.

     

    The
      bonds
      of 2007 Credit Agreement Series shall bear interest from their date as set
      forth
      in the Bond Form. Interest on the bonds of 2007 Credit Agreement Series shall
      be
      payable on each Interest Payment Date (as defined below), commencing on the
      first Interest Payment Date next succeeding the date of the bonds of 2007 Credit
      Agreement Series. If the Maturity Date falls on a day which is not a Business
      Day, as defined below, principal and any interest and/or fees payable by the
      Company with respect to the Maturity Date will be paid on the next succeeding
      Business Day. 

     

    Both
      the
      principal of and the interest on the bonds of 2007 Credit Agreement Series
      shall
      be payable at the times and in the manner set forth in the form of bond set
      out
      herein and in immediately available funds at the office or agency of the
      Trustee, 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. 

     

    Section
      1.2  Anything
      contained in Section 14 of Article I of the Indenture, or elsewhere in the
      Indenture, to the contrary notwithstanding, only the person in whose name bonds
      of 2007 Credit Agreement Series are registered (the “Registered
      Owner”)
      at the
      close of business on the Record Date (as defined below) with respect to any
      Interest Payment Date shall be entitled to receive the interest payable on
      such
      Interest Payment Date notwithstanding the cancellation of such bonds upon any
      transfer or exchange subsequent to the Record Date and prior to such Interest
      Payment Date; provided,
      however,
      that if
      and to the extent the Company shall default in the payment of the interest
      due
      on such Interest Payment Date, such defaulted interest shall be paid to the
      persons in whose names outstanding bonds of 2007 Credit Agreement Series are
      registered on the Record Date to be established by the Trustee for payment
      of
      such defaulted interest.

     

    The
      obligation of the Company to make payments with respect to principal under
      the
      Credit Agreement shall not give rise to an obligation to pay principal of the
      2007 Credit Agreement Series Bonds except on the Maturity Date of the Company
      or
      upon redemption as provided in this Supplemental Indenture. If at any time
      any
      permanent reduction of the Borrower Sublimit (as defined in the Credit
      Agreement) of the Company or the Borrower Credit Exposure (as defined in the
      Credit Agreement) of the Company shall result in the principal of the 2007
      Credit Agreement Series Bonds being greater than the greater of the Borrower
      Sublimit and the Borrower Credit Exposure, a payment obligation with respect
      to
      the principal of the 2007 Credit Agreement Series Bonds in the amount of such
      excess shall be deemed discharged upon the effectiveness of such permanent
      reduction. No payment of principal under the Credit 

     

    
      
        
        

      

      
        9

        
          

        

      

      
        
        

      

    

     

     

    Agreement
      shall reduce the principal amount of the 2007
      Credit Agreement Series Bonds to an amount less than the greater of the Borrower
      Sublimit and the Borrower Credit Exposure.

     

    The
      obligation of the Company to make payments with respect to the interest on
      the
      bonds of 2007 Credit Agreement Series shall be fully or partially, as the case
      may be, satisfied and discharged to the extent that, at the time that any such
      payment shall be due, the then due interest and/or fees of the Company under
      the
      Credit Agreement shall have been fully or partially paid. Satisfaction of any
      obligation to the extent that payment is made with respect to the interest
      and/or fees of the Company under the Credit Agreement means that if any payment
      is made on the interest and/or fees of the Company under the Credit Agreement,
      a
      corresponding payment obligation with respect to the interest on the bonds
      of
      2007 Credit Agreement Series shall be deemed discharged in the same amount
      as
      such payment made on the interest and/or fees of the Company under the Credit
      Agreement.

     

    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 and interest
      on
      the bonds of 2007 Credit Agreement Series, so far as such payments at the time
      have become due, has been fully satisfied and discharged pursuant to the
      foregoing paragraphs unless and until the Trustee shall have received a written
      notice from the Agent stating (i) that timely payment of principal of or
      interest on the bonds of 2007 Credit Agreement Series has not been made, (ii)
      that the Company is in arrears as to the payments required to be made by it
      to
      the Agent in connection with the Company Obligations pursuant to the Credit
      Agreement, and (iii) the amount of the arrearage.

     

    Section
      1.3  As
      used
      herein, (A) “Business
      Day”
shall
      have the meaning assigned thereto in the Credit Agreement; (B) “Interest
      Payment Date”
shall
      mean each date on which Company Obligations constituting interest and/or fees
      are due and payable from time to time pursuant to the Credit Agreement; (C)
      “Interest
      Rate”
shall
      mean a rate of interest per annum, adjusted as necessary, to result in an
      interest payment equal to the aggregate amount of Company Obligations
      constituting interest and fees of the Company due under the Credit Agreement
      on
      the applicable Interest Payment Date; and (D) “Record
      Date”
with
      respect to any Interest Payment Date shall mean the day (whether or not a
      Business Day) immediately next preceding such Interest Payment
      Date.

     

    Section
      1.4  Except
      as
      set forth herein, the bonds of 2007 Credit Agreement Series are not redeemable.
      Upon the occurrence of a Default by the Company under the Credit Agreement
      and
      the acceleration of the Company Obligations, the bonds of 2007 Credit Agreement
      Series shall be redeemable in whole upon receipt by the Trustee of a written
      demand from the Agent stating that there has occurred under the Credit Agreement
      both a Default by the Company and a declaration of acceleration of the Company
      Obligations and demanding redemption of the bonds of 2007 Credit Agreement
      Series (including a description of the amount of principal, interest, fees,
      cash
      collateralization obligations and other amounts which comprise such Company
      Obligations). The Company waives any right it may have to prior notice of such
      redemption under the Indenture and any other notice required under the
      Indenture, including notice to be given by the Company, shall be deemed
      satisfied by the notice given by the Agent as aforesaid. Upon surrender of
      the
      bonds of 2007 Credit Agreement Series by the Agent to the Trustee, the bonds
      of
      2007 Credit Agreement Series shall be redeemed at a redemption price equal
      to
      the aggregate amount of the Company Obligations.

     

    
      
        
        

      

      
        10

        
          

        

      

      
        
        

      

    

    Section
      1.5  The
      bonds
      of 2007 Credit Agreement Series shall not be assignable or transferable except
      to a successor Agent appointed in accordance with the Credit Agreement. The
      bonds of 2007 Credit Agreement Series are
      exchangeable by the Registered Owner thereof, in person or by attorney duly
      authorized, at the principal office or place of business of the Trustee under
      the Indenture, upon the surrender and cancellation of said bonds and the payment
      of any stamp tax or other governmental charge, and upon any such exchange a
      new
      registered bond or bonds without coupons, of the same series and maturity and
      for the same aggregate principal amount, will be issued in exchange theretofore;
      provided, that the Company shall not be required to exchange any bonds of 2007
      Credit Agreement Series for a period of ten (10) days next preceding an Interest
      Payment Date with respect to such bonds.

     

    Section
      1.6  The
      bonds
      of 2007 Credit Agreement Series
      shall, from time to time, be executed on behalf of the Company and sealed with
      the corporate seal of the Company, all in the manner provided or permitted
      by
      Section 6 of Article I of the Indenture, as follows:

     

    (a)  bonds
      of
      2007 Credit Agreement Series executed on behalf of the Company by its President
      or a Vice-President and/or by its Secretary or an Assistant Secretary may be
      so
      executed by the facsimile signature of such President or Vice-President and/or
      of such Secretary or Assistant Secretary, as the case may be, of the Company,
      or
      of any person or persons who shall have been such officer or officers, as the
      case may be, of the Company on or subsequent to the date of this supplemental
      indenture, notwithstanding that he or they may have ceased to be such officer
      or
      officers of the Company at the time of the actual execution, authentication,
      issue or delivery of any of such bonds, and any such facsimile signature or
      signatures of any such officer or officers on any such bonds shall constitute
      execution of such bonds on behalf of the Company by such officer or officers
      of
      the Company for the purposes of the Indenture, as hereby amended, and shall
      be
      valid and effective for all purposes, provided that all bonds shall always
      be
      executed on behalf of the Company by the signature, manual or facsimile, of
      its
      President or a Vice-President and of its Secretary or an Assistant Secretary,
      and provided, further, that none of such bonds shall be executed on behalf
      of
      the Company by the same officer or person acting in more than one capacity;
      and

     

    (b)  such
      corporate seal of the Company may be a facsimile, and any bonds of 2007 Credit
      Agreement Series on which such facsimile seal shall be affixed, impressed,
      imprinted or reproduced shall be deemed to be sealed with the corporate seal
      of
      the Company for the purposes of the Indenture, as hereby amended, and such
      facsimile seal shall be valid and effective for all purposes.

     

    Section
      1.7  As
      provided in Section 8.4 of the Credit Agreement, the Agent shall surrender
      the
      bonds of 2007 Credit Agreement Series to the Trustee for cancellation when
      each
      of the Borrower Sublimit and the Borrower Credit Exposure have been reduced
      to
      zero and all fees and other amounts payable by the Company pursuant to the
      Credit Agreement with respect to the Company Obligations shall have been duly
      paid.

     

    
      
        
        

      

      
        11

        
          

        

      

      
        
        

      

    

    Article
      II   

     

    Section
      2.1  Sections
      10 and 16 of Article III of the Indenture are, and each of them is, hereby
      amended by striking out the words “Series
      1997-2, Senior Notes Series AA-1, Senior Notes Series AA-2, Senior Notes Series
      BB, Environmental Improvement Series 2004, Senior Notes Series CC and 2006
      Credit Agreement Series”
      wherever the same occur in each of said sections, and by inserting, in lieu
      thereof, the words “Series
      1997-2, Senior Notes Series AA-1, Senior Notes Series AA-2, Senior Notes Series
      BB, Environmental Improvement Series 2004, Senior Notes Series CC, 2006 Credit
      Agreement Series and 2007 Credit Agreement Series”
and
      the
      Company hereby covenants and agrees to observe and comply with the provisions
      of
      said sections as hereby amended.

     

    Article
      III   

     

    Section
      3.1  The
      provisions of this supplemental indenture shall become and be effective from
      and
      after the execution hereof, and the Indenture, as hereby amended, shall remain
      in full force and effect.

     

    Section
      3.2  Each
      reference in the Indenture, or in this supplemental indenture, to any article,
      section, term or provision of the Indenture shall mean and be deemed to refer
      to
      such article, section, term or provision of the Indenture, as hereby amended,
      except where the context otherwise indicates.

     

    Section
      3.3  All
      the
      covenants, provisions, stipulations and agreements in this supplemental
      indenture contained are and shall be for the sole and exclusive benefit of
      the
      parties hereto, their successors and assigns, and of the holders and Registered
      Owners from time to time of the bonds of 2007 Credit Agreement Series and of
      the
      coupons issued and outstanding from time to time under and secured by the
      Indenture, as hereby amended, and the Agent, for the benefit of the Lenders
      under the Credit Agreement.

     

    This
      supplemental indenture has been executed in a number of identical counterparts,
      each of which so executed shall be deemed to be an original.

     

    At
      the
      time of the execution of this supplemental indenture, the aggregate principal
      amount of all indebtedness of the Company outstanding, or to be presently
      outstanding, under and secured by the Indenture, as hereby amended, is
      $496,500,000, evidenced by First Mortgage Bonds of the series listed below,
      issued by the Company under said Indenture and now outstanding or to be
      presently issued by it under said Indenture, as follows:

     


    
      
        
        

      

      
        12

        
          

        

      

      
        
        

      

    


    
 

     

    
      	
               

                                                          
                Series                                     
                

            	
               

                                   
                Interest Rate
                (%)                
                

            	
               

                                               
                Maturity
                Date                             
                

            	
              Principal

                                     
                Amount
                ($)                  
                

            
	
               

            	 	 	 
	
              1997-2

            	
              7.61

            	
              June
                1, 2017

            	
              40,000,000

            
	
              Senior
                Notes AA-1

            	
              5.375

            	
              December
                15, 2008

            	
              15,000,000

            
	
              Senior
                Notes AA-2

            	
              6.125%

            	
              December
                15, 2028

            	
              60,000,000

            
	
              Senior
                Notes BB

            	
              6.625%

            	
              June
                15, 2011

            	
               
                150,000,000

            
	
              Series
                2004

            	
              * 

            	
              July
                1, 2025

            	
              35,000,000
                

            
	
              Senior
                Notes CC 

            	
              6.70%

            	
              June
                15, 2036

            	
              61,500,000  
                

            
	
              2006
                Credit Agreement

            	
              **

            	
              **

            	
               
                135,000,000

            
	
              2007
                Credit Agreement

            	
              ***

            	
              ***

            	
              0(a)

            
	
               

            	 	 	 
	 	 	
              Total........

            	
                                   
                 496,500,000

            


    

    


     

    Section
      3.4  The
      Company acknowledges and intends that all advances made to it by the Lenders
      under the Credit Agreement, including future advances whenever hereafter made,
      shall be a lien from the time this Supplemental Indenture is
      recorded, as provided in Section 15-1302(b)(1) of the Illinois Mortgage
      Foreclosure Law (the “Act”), 735 ILCS 15-1101, et seq. The amount of the bonds
      of the 2007 Credit Agreement Series which comprises the principal amount then
      outstanding of the Obligations under the Credit Agreement constitutes revolving
      credit indebtedness secured by a mortgage on real property, pursuant to the
      terms and conditions of 205 ILCS 5/5d from the date of this Supplemental
      Indenture.

     

    


     

    

      

      
        *
          As
          determined in accordance with the Indenture of Trust dated as of October
          1, 2004
          between the Illinois Finance Authority and UMB Bank, N.A., as
          Trustee.

         

        **
          As
          determined in accordance with the Credit Agreement dated as of July 14,
          2006
          among the Company and the other Borrowers identified therein and JPMorgan
          Chase,
          N.A. as agent.

         

        ***
          As
          determined in accordance with the Credit Agreement.

         

        (a)
          To be
          issued by the Company under said Indenture from time to time under this
          Supplemental Indenture in the amounts as provided in the Credit Agreement
          but
          only upon surrender of an equal amount of bonds of the 2006 Credit Agreement
          Series. 

         

      

    




    In
      WITNESS WHEREOF, said Central Illinois Public Service Company has caused this
      instrument to be executed in its corporate name by its President or a Vice
      President and its corporate seal or a facsimile thereof to be hereunto affixed
      and to be attested by its Secretary or an Assistant Secretary, and said U.S.
      Bank National Association, for the purpose of entering into and joining with
      the
      Company in the execution of this supplemental indenture, has caused this
      instrument to be executed in its corporate name by one of its Vice Presidents
      and its corporate seal to be hereunto affixed and to be attested by one of
      its
      Assistant Vice Presidents, and said Richard Prokosch, for the purpose of
      entering into and joining with the Company in the execution of this supplemental
      indenture, has signed and sealed this instrument; all as of the day and year
      first above written.

     

    
      	 	
              Central
                Illinois Public Service Company

               

              By       
                /s/
                Jerre E.
                Birdsong                          

              Name:
                Jerre E. Birdsong 

              Title:
                Vice President and Treasurer 

            
	
              (Corporate
                Seal)

               

              Attest:

               

              By:     
                /s/
                G.L.
                Waters             
                  

              Name:
                G.L.Waters

              Title:
                Assistant Secretary

            	 


    


    
      
        
        

      

      
        13

        
          

        

      

      
        
        

      

    


    


    
      	 	 
	 	
              U.S.
                Bank National Association

              
              

               

              By:     
                /s/
                Richard Prokosch         
                     

              Name:
                Richard Prokosch 

              Title:  
                Vice
                President

            
	
              (Corporate
                Seal)

               

              Attest:

               

              By:      
                /s/
                Darlene Garsteig        
                

              Name:
                Darlene Garsteig

              Title: Assistant
                Vice President

            	 
	 	
               

               

              By:         
                /s/
                Richard Prokosch (Seal) 

              Richard
                Prokosch 

            


    


    
      
        
        

      

      
        
        

        
          

        

      

      
        
        

      

    


    


    State
      of
      Missouri  )

    ) SS

    City
      of
      St. Louis   )

     

    I,
      Carol
      A. Head, a Notary Public, do hereby certify that Jerre E. Birdsong, Vice
      President and Treasurer of Central Illinois Public Service Company, a
      corporation organized and existing under the laws of the State of Illinois,
      and
      G.L. Waters, Assistant Secretary of said corporation, who are both personally
      known to me to be the same persons whose names are subscribed to the foregoing
      instrument as such officers, respectively, of said corporation, and who are
      both
      personally known to me to be such officers, appeared before me this day in
      person and severally acknowledged that they signed, sealed and delivered said
      instrument as their free and voluntary act as such officers, and as the free
      and
      voluntary act of said corporation, for the uses and purposes therein set
      forth.

     

    Given
      under my hand and official seal this 5th day of March 2007, in the City and
      State aforesaid.

     

    
      	 	
               

               

              /s/
                Carol A. Head      

            
	 	
              Carol
                A. Head

              Notary
                Public

            
	
              (Notarial
                Seal)

            	 


    

    


    My
      commission expires 11-20-2010


    
      
        
        

      

      
        
        

        
          

        

      

      
        
        

      

    


    


    State
      of
      Minnesota  )

    ) SS

    County
      of
      Ramsey   )

     

    I,
      L.
      Elaine Eby, a Notary Public in and for Ramsey County in the State aforesaid,
      do
      hereby certify that:

     

    (a)
      Richard Prokosch, a Vice President of U.S. Bank National Association, a national
      banking association, and Darlene Garsteig, an Assistant Vice President of said
      association, who are both personally known to me to be the same persons whose
      names are subscribed to the foregoing instrument as such officers, respectively,
      of said association, and who are both personally known to me to be such
      officers, appeared before me this day in person and severally acknowledged
      that
      they signed, sealed and delivered said instrument as their free and voluntary
      act as such officers, and as the free and voluntary act of said association,
      for
      the uses and purposes therein set forth; and

     

    (b)
      Richard Prokosch, personally known to me to be the same person whose name is
      subscribed to the foregoing instrument, appeared before me this day in person
      and acknowledged that he signed, sealed and delivered said instrument as his
      free and voluntary act, for the uses and purposes therein set
      forth.

     

    


     

    Given
      under my hand and official seal this 5th day of March, 2007.

     

    
      	 	
               

               

              /s/
                L. Elaine Eby 


              L.
                Elaine Eby

              Notary
                Public

            
	 	 
	
              (Notarial
                Seal)

            	 


    

    


    My
      Commission expires: January 31, 2010