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                                                                 EXHIBIT 10.26.2


                        RATIFICATION OF AND AMENDMENT TO
                     ACT OF MORTGAGE AND SECURITY AGREEMENT

      This instrument, dated effective as of the 28th day of December, 2004, is
by F-W OIL EXPLORATION L.L.C., a Delaware limited liability company (herein,
"Mortgagor"), whose Taxpayer Identification Number is 76-0688905, the address
for which for all purposes hereof is 9821 Katy Freeway, Suite 1050, Houston,
Texas 77024, and GUARANTY BANK, FSB, a Federal savings bank, as Agent for the
Lenders identified in the Credit Agreement as defined below, and the mailing
address for which is 333 Clay Street, Suite 4400, Houston, Texas 77002-4103
(herein "Mortgagee").

                              W I T N E S S E T H:

      WHEREAS, Mortgagor has heretofore executed certain security instruments
more particularly described in Exhibit A attached hereto and incorporated herein
for all purposes by this reference (the "Security Instruments," whether one or
more); and

      WHEREAS, the Security Instruments were executed and delivered to secure
the payment or performance of certain indebtedness and other obligations of
Mortgagor, as more fully described in said instruments (the "Secured
Indebtedness"); and

      WHEREAS, pursuant to the Credit Agreement by and between Mortgagor and
Mortgagee, dated effective as of December 28, 2004 (as amended, restated, or
supplemented from time to time, the "Credit Agreement"), the parties desire to
amend the Security Instruments as described below;

      NOW, THEREFORE, in consideration of the foregoing, the benefits to be
derived by Mortgagor and other good and valuable consideration, the receipt and
sufficiency of which are hereby acknowledged by Mortgagor, the parties hereto
agree as follows, with capitalized terms used but not defined herein having
meanings assigned to such terms in the Credit Agreement:

            1.    AMENDMENTS.

                  (a) AMENDMENT OF CREDIT AGREEMENT. All references to the
      Credit Agreement in the Security Instruments are hereby amended to refer
      to the Credit Agreement as defined above.

                  (b) AMENDMENT OF SECURED INDEBTEDNESS. The Secured
      Indebtedness as defined in the Security Instruments is hereby amended to
      delete Section 3.1.A and to substitute therefor the following:

            A. The Obligations, including, without limitation, (a) the
      indebtedness evidenced by the Credit Agreement, and (b) the Promissory
      Note executed by Mortgagor to the order of the Lender pursuant to the
      Credit Agreement in the aggregate face amount of up to $50,000,000,
      bearing interest and payable as therein provided or as provided in the
      Credit Agreement.

            2. WARRANTIES, REPRESENTATIONS, AND COVENANTS. The warranties,
      representations and covenants of Mortgagor contained in the Security

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      Instruments are hereby remade by Mortgagor to Mortgagee and are in full
      force and effect as of the date hereof.

            3. REAFFIRMATION OF SECURITY INSTRUMENTS. To secure the Secured
      Indebtedness, Mortgagor has granted, bargained, sold, mortgaged, assigned,
      transferred and conveyed, and by these presents does grant, bargain, sell,
      mortgage, assign, transfer and convey, unto the Mortgagee, and grants to
      Mortgagee a security interest in, all of Mortgagor's right, title and
      interest, whether now owned or hereafter acquired, in and to the
      Encumbered Property, including, without limitation, the oil, gas and
      mineral interests described in Exhibit B and personalty associated
      therewith.

            4. MISCELLANEOUS. This instrument shall be considered as an
      amendment to and ratification of the Security Instruments, and the
      Security Instruments, as herein expressly amended, are hereby ratified,
      approved and confirmed in every respect. All liens created, extended or
      renewed by the Security Instruments are hereby extended, renewed and
      carried forward by this instrument and incorporated herein. All references
      to the Security Instruments in any documents heretofore or hereafter
      executed shall be deemed to refer to the Security Instruments as amended
      by this instrument.

      For the convenience of the parties, this instrument may be executed in
multiple counterparts. Each of the counterparts hereof so executed shall for all
purposes be deemed to be an original, and all such counterparts shall together
constitute but one and the same instrument.

      IN WITNESS WHEREOF, Mortgagor and Mortgagee have executed this instrument
on the dates of their respective acknowledgments below but effective as of the
date first above written.

                  [REMAINDER OF PAGE INTENTIONALLY LEFT BLANK]

                                     -2-
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      THUS SIGNED in multiple originals in my office in Houston, Harris County,
Texas, by the person who appears above my signature below in the presence of the
undersigned competent witnesses who have signed their names hereto with the said
appearer, and me, Notary, on the 28th day of December, 2004, after due reading
of the whole.

WITNESSES TO SIGNATURE OF MORTGAGOR:  MORTGAGOR

/s/ James F. Gilbert                  F-W OIL EXPLORATION L.L.C.
---------------------------------
(Signature)

                                      By: Jim R. Brock
/s/ James F. Gilbert                      --------------------------------------
---------------------------------         Jim R. Brock
(Printed Name)                            President and CFO
                                          Taxpayer Identification No. 76-0688905
/s/ Glinda B. Collins
---------------------------------
(Signature)

/s/ Glinda B. Collins
---------------------------------
(Printed Name)

                   Mary Phares
                   -------------------------------------------
                   Notary Public in and for the State of Texas

                              [NOTARY PUBLIC LOGO]

                                  MARY PHARES
                         Notary Public, State of Texas
                             My Commission Expires
                               September 16, 2005


                                     -3-
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         THUS SIGNED in multiple originals in my office in Houston, Harris
County, Texas, by the person who appears above my signature below in the
presence of the undersigned competent witnesses who have signed their names
hereto with the said appearer, and me, Notary, on the 28th day of December,
2004, after due reading of the whole.

WITNESSES TO SIGNATURE OF MORTGAGEE:  MORTGAGEE

/s/ Jonathan Gregory                  GUARANTY BANK, FSB, AGENT
------------------------------------
(Signature)

Jonathan Gregory                      By: Arthur R. Gralla
------------------------------------      -----------------------
(Printed Name)                            Arthur R. Gralla, Jr.,
                                          Managing Director
                                          Taxpayer Identification No. 74-2511478
/s/ William J. Tom
------------------------------------
(Signature)

William J. Tom
------------------------------------
(Printed Name)

                   Kim Link
                   -------------------------------------------
                   Notary Public in and for the State of Texas

                              [NOTARY PUBLIC LOGO]

                                    KIM LINK
                                 Notary Public
                                 STATE OF TEXAS
                            My Comm. Exp. 09-03-2007

                                     -4-
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                                    EXHIBIT A
                                       TO
                        RATIFICATION OF AND AMENDMENT TO
                     ACT OF MORTGAGE AND SECURITY AGREEMENT

                              SECURITY INSTRUMENTS

1.    Act of Mortgage and Security Agreement dated September 22, 2003, by F-W
      Oil Exploration L.L.C. to Guaranty Bank, FSB, Agent, filed and recorded as
      follows:

      JURISDICTION                      FILING DATA

      LOUISIANA

          Plaquemines Parish            Filed December 8, 2003, under Clerk's
                                        Entry No. 03008556, MOB 385, Page 443
          Minerals Management Service   Filed January 12, 2004, under OCS Filing
                                        Number G21142

2.    UCC-3 Financing Statement Amendment from F-W Oil Exploration L.L.C. to
      Guaranty Bank, FSB, as Agent (relating to Act of Mortgage), filed and
      recorded as follows:

      JURISDICTION                     FILING DATA

      DELAWARE

         Secretary of State            Filed January 9, 2004, as Financing
                                       Statement No. 40069445, amending Initial
                                       Financing Statement No. 32562083 filed
                                       October 2, 2003

                                       A-i