Exhibit 10.3

EXECUTION
COUNTERPART

AMENDMENT ONE

AMENDMENT ONE (this "Amendment") dated as of April 22, 2005 by and among EDISON MISSION ENERGY (the
"Borrower"), CITICORP NORTH AMERICA, INC., as Administrative Agent (in such capacity, the "Administrative
Agent") and each of the financial lending institutions party hereto (the "Lenders").

WHEREAS,
the Borrower, the Administrative Agent, the Issuing Lender party thereto and certain of the Lenders entered into a Credit Agreement dated as of April 27, 2004 (the
"Credit Agreement");

WHEREAS,
the Borrower has requested that the Lenders make certain changes to the components of the Interest Coverage Ratio and the types of cash equivalents in which the Borrower may
invest; and

WHEREAS,
the Lenders and the Administrative Agent are willing to agree to the amendments provided for in this Amendment on the terms and conditions hereof.

ACCORDINGLY,
the parties hereto agree as follows:

Section 1.Definitions.Except as otherwise defined in this Amendment, terms defined in the Credit
Agreement are used herein (and in the introductions and recitals hereto) as defined therein.

Section 2.Amendment to the Credit Agreement.Subject to the satisfaction of the conditions precedent
specified in Section 3 below, but effective as of the Amendment Effective Date (as defined below), the Credit Agreement shall hereby be amended as follows:



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""Cash Equivalent Investment" means, at any time:

(a)   any
evidence of Indebtedness, maturing not more than one year after such time, issued or guaranteed by the United States government or an agency thereof;

(b)   other
investments in securities or bank instruments rated at least "A" by S&P or "A2" by Moody's or "A-1" by S&P or "P-1" by Moody's and with
maturities of not more than one year; or

(c)   money
market funds that (i) comply with the criteria set forth in Securities and Exchange Commission Rule 2a-7 under the Investment Company Act
of 1940, as amended, and (ii) have portfolio assets of at least $1,000,000,000.";



2

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Section 3.Conditions Precedent.This Amendment shall not become effective until the date (the
"Amendment Effective Date") on which each of the following conditions precedent have been satisfied or will be satisfied contemporaneously with this
Amendment becoming effective:



Section 4.Miscellaneous.Except as expressly amended hereby, all of the terms and provisions of the
Credit Agreement are and shall remain unchanged and in full force and effect. This Amendment may be executed in any number of counterparts, all of which taken together shall constitute one and the
same instrument and any of the parties hereto may execute this Amendment by signing any such counterpart. This Amendment shall be governed by, and construed in accordance with, the law of the State of
New York.

3

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IN WITNESS WHEREOF, the parties hereto have caused this Amendment to be duly executed and delivered by their respective officers thereunto
duly authorized as of the day and year first above written.

| |  | EDISON MISSION ENERGY                                                               
| |  | ------------------------------------------------------------------------------------
| |  | By:                                                                                 
| |  | CITICORP NORTH AMERICA, INC.,
    as Administrative Agent, Issuing Lender and Lender
| |  | By:                                                                                 
| |  | CITIGROUP FINANCIAL PRODUCTS INC.                                                   
| |  | By:                                                                                 
| |  | JPMORGAN CHASE BANK                                                                 
| |  | By:                                                                                 
| |  | LEHMAN COMMERCIAL PAPER INC.                                                        
| |  | By:                                                                                 

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SCHEDULE 1.1(a) to First Amended and Restated Credit Agreement

DOMESTIC & EURODOLLAR OFFICES

|Name of Lender                                                                                       |  | Domestic Office                                                                     |  | Eurodollar Office                                                                  
|---------------------------------------------------------------------------------------------------- |  | ----------------------------------------------------------------------------------- |  | -----------------------------------------------------------------------------------
|Allied Irish Bank, p.l.c.                                                                            |  | 405 Park Ave.
4th Floor
New York, NY 10022                                          |  | Bankcentre,
Ballsbridge
Dublin 4, Ireland                                          
|Babson CLO Ltd. 2004-II                                                                              |  | 360 Madison Ave.
10th Floor, Suite 1
New York, NY 10017                             |  | 360 Madison Ave.
10th Floor, Suite 1
New York, NY 10017                            
|Canadian Imperial Bank of Commerce                                                                   |  | 300 Madison Avenue
5th Floor
New York, NY 10017                                     |  | 300 Madison Avenue
5th Floor
New York, NY 10017                                    
|Newcourt Capital USA INC.                                                                            |  | 1211 Avenue of the Americas
22nd Floor
New York, NY 10036                           |  | 1211 Avenue of the Americas
22nd Floor
New York, NY 10036                          
|Citicorp North America, Inc.                                                                         |  | 388 Greenwich Street
New York, NY 10013                                             |  | 388 Greenwich Street
New York, NY 10013                                            
|Citigroup Financial Products Inc.                                                                    |  | c/o Citigroup Global Markets Inc.
333 West 34th Street
9th Floor
New York, NY 10001 |  | c/o Citigroup Global Markets Inc.
333 West 34th Street
9th Floor
New York, NY 10001
|Credit Suisse First Boston                                                                           |  | 11 Madison Avenue
13th Floor
New York, NY 10010                                     |  | 11 Madison Avenue
13th Floor
New York, NY 10010                                    
|Erste Bank Der Oesterreichischen Sparkassen AG                                                       |  | 280 Park Avenue
West Building
New York, NY 10017                                    |  | 280 Park Avenue
West Building
New York, NY 10017                                   
|GE VFS Holdings Inc.                                                                                 |  | 120 Long Ridge
Stamford, CT 06927                                                   |  | 120 Long Ridge
Stamford, CT 06927                                                  
|Goldman Sachs Credit Partners L.P.                                                                   |  | 85 Broad St.
New York, NY 10004                                                     |  | 85 Broad St.
New York, NY 10004                                                    
|Loan Funding VII LLC and
Highland Floating Rate Advantage Fund
c/o Highland Capital Management, L.P. |  | 13455 Noel Rd.
Suite 1300
Dallas, TX 75240                                          |  | 13455 Noel Rd.
Suite 1300
Dallas, TX 75240                                         
|JPMorgan Chase Bank                                                                                  |  | 270 Park Avenue
New York, NY 10017                                                  |  | 270 Park Avenue
New York, NY 10017                                                 
|KBC Bank, N.V.                                                                                       |  | 125 West 55th Street
10th Floor
New York, NY 10019                                  |  | 125 West 55th Street
10th Floor
New York, NY 10019                                 
|                                                                                                     |  |                                                                                     |  |                                                                                    

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|Lehman Commercial Paper Inc.                                                                       |  | 745 7th Ave.
16th Floor
New York, NY 10019               |  | 745 7th Ave.
16th Floor
New York, NY 10019              
|-------------------------------------------------------------------------------------------------- |  | -------------------------------------------------------- |  | --------------------------------------------------------
|Merrill Lynch Capital Corporation                                                                  |  | 255 Vesey St.
New York, NY 10080                         |  | 255 Vesey St.
New York, NY 10080                        
|Nationwide Mutual Insurance Company and
Nationwide Life Insurance Company
c/o Nationwide Insurance |  | One Nationwide Plaza
1-33-05
Columbus, OH 43215          |  | One Nationwide Plaza
1-33-05
Columbus, OH 43215         
|Loan Funding III LLC
c/o Pacific Investment Management Company LLC                                 |  | 840 Newport Center Dr.
Suite 100
Newport Beach, CA 92660 |  | 840 Newport Center Dr.
Suite 100
Newport Beach, CA 92660
|The Royal Bank of Scotland PLC                                                                     |  | 101 Park Ave.
New York, NY 10178                         |  | 101 Park Ave.
New York, NY 10178                        
|UBS Loan Finance LLC                                                                               |  | 677 Washington Blvd.
6th Floor
South Stamford, CT 06901  |  | 677 Washington Blvd.
6th Floor
South Stamford, CT 06901 
|Union Bank of California, N.A.                                                                     |  | 445 S. Figueroa Street
15th Floor
Los Angeles, CA 90071  |  | 445 S. Figueroa Street
15th Floor
Los Angeles, CA 90071 
|Wells Fargo Bank, N. A.                                                                            |  | 707 Wilshire Blvd.
16th Floor
Los Angeles, CA 90017      |  | 707 Wilshire Blvd.
16th Floor
Los Angeles, CA 90017     
|WestLB AG, New York Branch                                                                         |  | 1211 Avenue of the Americas
New York, NY 10036           |  | 1211 Avenue of the Americas
New York, NY 10036          

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SCHEDULE 1.1(b)
to First Amended and Restated Credit Agreement

REVOLVER A COMMITMENTS

|Name of Lender                                 |  | Revolver A
Commitment
|---------------------------------------------- |  | ---------------------
|Credit Suisse First Boston                     |  | $                    
|Citicorp North America, Inc.                   |  | $                    
|WestLB AG, New York Branch                     |  | $                    
|JPMorgan Chase Bank                            |  | $                    
|KBC Bank, N.V.                                 |  | $                    
|Canadian Imperial Bank of Commerce             |  | $                    
|Lehman Commercial Paper Inc.                   |  | $                    
|UBS Loan Finance LLC                           |  | $                    
|Highland/Loan Funding VII LLC                  |  | $                    
|Union Bank of California, N.A.                 |  | $                    
|Nationwide Life Insurance Company              |  | $                    
|Nationwide Mutual Insurance Company            |  | $                    
|Babson CLO Ltd. 2004-II                        |  | $                    
|Erste Bank Der Oesterreichischen Sparkassen AG |  | $                    
|PIMCO/Loan Funding III                         |  | $                    
|Invesco/Loan Funding IX LLC                    |  | $                    
|Highland/Floating Rate Advantage Fund          |  | $                    

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SCHEDULE
1.1(c)
to First Amended and Restated Credit Agreement

REVOLVER B COMMITMENTS

|Name of Lender                     |  | Revolver B
Commitment
|---------------------------------- |  | ---------------------
|Citicorp North America, Inc.       |  | $                    
|Credit Suisse First Boston         |  | $                    
|Goldman Sachs Credit Partners L.P. |  | $                    
|JPMorgan Chase Bank                |  | $                    
|The Royal Bank of Scotland PLC     |  | $                    
|GE VFS Holdings Inc.               |  | $                    
|Lehman Commercial Paper Inc.       |  | $                    
|Merrill Lynch Capital Corporation  |  | $                    
|UBS Loan Finance LLC               |  | $                    
|Union Bank of California, N.A.     |  | $                    
|WestLB AG, New York Branch         |  | $                    
|Newcourt Capital USA INC.          |  | $                    
|Allied Irish Bank, p.l.c           |  | $                    
|Wells Fargo Bank, N.A.             |  | $                    

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SCHEDULE 2.2
to First Amended and Restated Credit Agreement

CLOSING DATE BANK ACCOUNTS

Account Number:

Name of Institution3866-0071

Citibank, N.A.3866-0098

Citibank, N.A.


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SCHEDULE
2.6.11
to First Amended and Restated Credit Agreement

REVOLVER B LETTERS OF CREDIT

|Beneficiary |  | LC
Number |  | USD Value |              | Effective
Date |           | Expiry
Date |          | Purpose
|----------- |  | --------- |  | --------- | ------------ | -------------- | --------- | ----------- | -------- | -------
|Travelers   |  | 61614287  |  | $         | 1,905,860.00 |                | 07-May-04 |             | 4-May-06 |        
|Exelon      |  | 61637564  |  | $         | 2,700,000.00 |                | 16-Feb-05 |             | 2-Jan-07 |        

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SCHEDULE 7.2.1(c) to First Amended and Restated Credit Agreement

CAPITALIZED LEASE LIABILITIES AND OPERATING LEASE LIABILITIES

Capitalized Lease Liabilities

None

Operating Lease Liabilities

Total Future
PaymentsEquipment

$
721,681Vehicles

$
1,684,018Railcar/Barge

$
120,229,460Lincoln Quarry

$
1,423,200TOTAL

$
124,058,359


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SCHEDULE
7.2.1(e)
to First Amended and Restated Credit Agreement

FIXED OR CAPITAL ASSET PLANNED ACQUISITION,  CONSTRUCTION OR IMPROVEMENT

|Unit              |  | Project                                    |  | Year      |  | Amount
|----------------- |  | ------------------------------------------ |  | --------- |  | ------
|Crawford 7        |  | Upgrade pulverizers                        |  | 2005      |  | $     
|Crawford 7        |  | Upgrade coal dust collection               |  | 2005      |  | $     
|Fisk 19           |  | Upgrade distributed control system         |  | 2005      |  | $     
|Fisk Plant        |  | Upgrade coal dust collection               |  | 2005      |  | $     
|Joliet 7          |  | Install generator static exciter           |  | 2005      |  | $     
|Joliet 7          |  | Install electrostatic precipitator rappers |  | 2005      |  | $     
|Powerton 5        |  | Upgrade air preheater baskets              |  | 2005      |  | $     
|Powerton Plant    |  | Upgrade coal dust collection               |  | 2005      |  | $     
|Waukegan Plant    |  | Replace soot blowing air compressors       |  | 2005      |  | $     
|Waukegan 7        |  | Upgrade pulverizers                        |  | 2006
2008 |  | $$    
|Waukegan 8        |  | Upgrade pulverizers                        |  | 2006
2007 |  | $$    
|Will County Plant |  | Upgrade coal dust collection               |  | 2005      |  | $     
|Will County 3     |  | Water induction prevention equipment       |  | 2005      |  | $     

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