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                                                                    EXHIBIT 4.11

                        AMENDMENT NO. 4 TO SECOND AMENDED
                          AND RESTATED CREDIT AGREEMENT

  This AMENDMENT NO. 4 TO SECOND AMENDED AND RESTATED CREDIT AGREEMENT
("Amendment") dated as of April 21, 2003 (the "Amendment Effective Date") is
among Edge Petroleum Corporation, a Delaware corporation ("Parent"), Edge
Petroleum Exploration Company, a Delaware corporation ("Edge Exploration"), Edge
Petroleum Operating Company, Inc., a Texas corporation ("Edge Operating," and
together with the Parent and Edge Exploration referred to collectively as the
"Borrowers"), the lenders party to the Credit Agreement (as defined below) from
time to time (the "Lenders"), and Union Bank of California, N.A., as agent for
the Lenders ("Agent").

                                    RECITALS

A.       The Borrowers, the Lenders and the Agent are parties to the Second
        Amended and Restated Credit Agreement dated as of October 6, 2000, as
        amended by (1) Amendment No. 1 and Waiver dated as of November 21, 2001,
        (2) Amendment No. 2 to Second Amended and Restated Credit Agreement
        dated as of May 29, 2002, and (3) Amendment No. 3 to Second Amended and
        Restated Credit Agreement dated as of August 8, 2002 (as so amended, the
        "Credit Agreement"; the defined terms of which are used herein otherwise
        defined herein).

B.       The Borrowers, the Lenders and the Agent wish to, subject to the terms
       and conditions of this Amendment, amend the Credit Agreement in order to
       (1) increase the Commitment and (2) increase the Borrowing Base.

  THEREFORE, the Borrowers, the Lenders and the Agent hereby agree as follows:

SECTION 1. DEFINED TERMS; OTHER DEFINITIONAL PROVISIONS. As used in this
         Amendment, each of the terms defined in the opening paragraph and the
         Recitals above shall have the meanings assigned to such terms therein.
         The words "hereby", "herein", "hereinafter", "hereof", "hereto" and
         "hereunder" when used in this Amendment shall refer to this Amendment
         as a whole and not to any particular Article, Section, subsection or
         provision of this Amendment. All titles or headings to Articles,
         Sections, subsections or other divisions of this Amendment or the
         exhibits hereto, if any, are only for the convenience of the parties
         and shall not be construed to have any effect or meaning with respect
         to the other content of such Articles, Sections, subsections, other
         divisions or exhibits, such other content being controlling as the
         agreement among the parties hereto. Whenever the context requires,
         reference herein made to the single number shall be understood to
         include the plural; and likewise, the plural shall be understood to
         include the singular. Words denoting sex shall be construed to include
         the masculine, feminine and neuter, when such construction is
         appropriate; and specific enumeration shall not exclude the general but
         shall be construed as cumulative.

SECTION 2. COMMITMENT. The definition of "Commitment" in Section 1.2 is deleted
         in its entirety and replaced with the following:

                 "Commitment" shall mean, for Union Bank of California, N.A.,
                 $40,000,000, or if such Lender has entered into any Lender
                 Assignment Agreement after the date of this Agreement, the
                 amount set forth for such Lender as its Commitment in the
                 Register maintained by the Agent pursuant to Section 9.1(c), as
                 such amount may be reduced pursuant to Section 2.12.

SECTION 3. INCREASE IN BORROWING BASE. The Borrowing Base shall, effective as
         of the Amendment Effective Date, be increased from $25,000,000 to
         $26,500,000 and shall remain in effect at that level until the
         Borrowing Base is redetermined in accordance with the terms of the
         Credit Agreement.

SECTION 4. REPRESENTATIONS AND WARRANTIES. The Borrowers hereby represent and
         warrant that: (a) except for such representations which are made only
         as of a prior date, the representations and warranties set forth in

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         the Credit Agreement and in the other Loan Documents are true and
         correct in all respects as of the Amendment Effective Date as if made
         on and as of such date; (b) the execution, delivery and performance of
         this Amendment and any Loan Documents executed and delivered in
         connection with this Amendment are within the corporate power and
         authority of each Borrower and have been duly authorized by appropriate
         corporate action and proceedings; (c) this Amendment and the Loan
         Documents executed in connection with this Amendment constitute legal,
         valid, and binding obligations of the Borrower party hereto and
         thereto, enforceable in accordance with their terms, except as limited
         by applicable bankruptcy, insolvency, reorganization, moratorium, or
         similar laws affecting the rights of creditors generally and general
         principles of equity; and (d) there are no governmental or other third
         party consents, licenses and approvals required in connection with the
         execution, delivery, performance, validity and enforceability of this
         Amendment and such other Loan Documents.

SECTION 5. CONDITIONS. This Amendment shall become effective and enforceable
         against the parties hereto and the Credit Agreement shall be amended as
         provided herein upon the occurrence of the following conditions
         precedent on or before the Amendment Effective Date:

            (a)   Amendment. The Agent shall have received multiple original
                  counterparts of this Amendment duly and validly executed and
                  delivered by duly authorized officers of the Borrowers, the
                  Agent and the Lenders.

            (b)   New Note. The Borrowers shall have executed and delivered an
                  amended and restated promissory note dated the date hereof in
                  the amount of the new Commitment.

            (c)   Other Instruments or Documents. The Agent and the Lenders
                  shall have received the Security Instruments and such other
                  instruments, documents and amendments to the Security
                  Instruments as any of them may reasonably request.

            (d)   No Default. No Default shall have occurred and be continuing
                  as of the Amendment Effective Date.

            (e)   Fees. The Borrowers shall have paid (i) a Borrowing Base
                  increase fee in the amount of $7,500 as required under Section
                  2.15 of the Credit Agreement, (ii) an engineering fee in the
                  amount of $5,000 as required under Section 2.17 of the Credit
                  Agreement, and (iii) all fees and expenses of the Agent's
                  outside legal counsel and other consultants pursuant to all
                  invoices presented for payment on or prior to the Amendment
                  Effective Date.

SECTION 6. MISCELLANEOUS.

            (a)   Effect on Loan Documents. Each of the Borrowers, the Lenders
                  and the Agent does hereby adopt, ratify, and confirm the
                  Credit Agreement, as amended hereby, and acknowledges and
                  agrees that the Credit Agreement, as amended hereby, is and
                  remains in full force and effect. Nothing herein shall act as
                  a waiver of any of the Agent's or the Lender's rights under
                  the Loan Documents, as amended. From and after the Amendment
                  Effective Date, all references to the Credit Agreement and the
                  Loan Documents shall mean such Credit Agreement and such Loan
                  Documents as amended by this Amendment. This Amendment is a
                  Loan Document for the purposes of the provisions of the other
                  Loan Documents. Without limiting the foregoing, any breach of
                  representations, warranties, and covenants under this
                  Amendment shall be an Event of Default under the Credit
                  Agreement.

            (b)   Counterparts. This Amendment may be signed in any number of
                  counterparts, each of which shall be an original and all of
                  which, taken together, constitute a single instrument. This
                  Amendment may be executed by facsimile signature and all such
                  signatures shall be effective as originals.

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            (c)   Successors and Assigns. This Amendment shall be binding upon
                  and inure to the benefit of the parties hereto and their
                  respective successors and assigns permitted pursuant to the
                  Credit Agreement.

            (d)   Invalidity. In the event that any one or more of the
                  provisions contained in this Amendment shall for any reason be
                  held invalid, illegal or unenforceable in any respect, such
                  invalidity, illegality or unenforceability shall not affect
                  any other provision of this Amendment.

            (e)   Governing Law. This Amendment shall be deemed to be a contract
                  made under and shall be governed by and construed in
                  accordance with the laws of the State of Texas.

THIS AMENDMENT, THE CREDIT AGREEMENT AS AMENDED BY THIS AMENDMENT, THE NOTES,
AND THE OTHER LOAN DOCUMENTS CONSTITUTE THE ENTIRE UNDERSTANDING AMONG THE
PARTIES HERETO WITH RESPECT TO THE SUBJECT MATTER HEREOF AND SUPERSEDE ANY PRIOR
AGREEMENTS, WRITTEN OR ORAL, WITH RESPECT THERETO.

                         [SIGNATURES BEGIN ON NEXT PAGE]

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           EXECUTED effective as of the date first above written.

                                    BORROWERS:

                                    EDGE PETROLEUM CORPORATION

                                    By: /s/ Michael G. Long
                                        ----------------------------------------
                                        Michael G. Long, Chief Financial Officer

                                    EDGE PETROLEUM EXPLORATION COMPANY

                                    By: /s/ Michael G. Long
                                        ------------------------------------
                                    Michael G. Long, Chief Financial Officer

                                    EDGE PETROLEUM OPERATING COMPANY, INC.

                                    By: /s/ Michael G. Long
                                        ----------------------------------------
                                        Michael G. Long, Chief Financial Officer

                                    AGENT AND SOLE LENDER:

                                    UNION BANK OF CALIFORNIA, N.A., as
                                    Agent and as a Lender

                                    By: /s/ Damien Meiburger
                                        ----------------------------------------
                                           Damien Meiburger
                                           Senior Vice President

                                    By: /s/ Randall Osterberg
                                        ----------------------------------------
                                    Name:  Randall Osterberg
                                    Title: Senior Vice President

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