AMENDMENT TO
                            STOCK PURCHASE AGREEMENT

      THIS AMENDMENT TO STOCK PURCHASE AGREEMENT (the "Amendment") is entered
into effective this 17th day of May 2004, by and among Itera Holdings BV
("Buyer"), Dune Energy, Inc. ("Seller"), and Vaquero Partners, LLC ("LLC").

                                   WITNESSETH:

      WHEREAS, Seller, Buyer and LLC have entered into that certain Stock
Purchase Agreement dated May 10th, 2004; and

      WHEREAS, Seller, Buyer and LLC have agreed to modify and amend the
Agreement;

      NOW, THEREFORE, in consideration of the agreements hereinafter set forth
and for Ten Dollars ($10.00) and other good and valuable consideration, the
receipt and sufficiency of which are hereby acknowledged, Seller, Buyer and LLC
agree as follows:

      1. Recitals. The foregoing recitals are true and correct and are
incorporated herein by reference.

      2. Defined Terms. All capitalized terms used herein and not expressly
defined shall have the meaning given to them in the Agreement.

      3. Amendments. The following amendments to the Agreement are hereby
incorporated into the Agreement:

      a. The last sentence of Recital B of the Agreement is hereby restated by
substituting "70,928,793" for "70,016,725".

      b. Section 1.4 is hereby restated to read as follows: "The parties
acknowledge that Buyer has (i) already paid to company the sum of $821,000 and
(ii) agreed to pay the Company an additional $179,000 (collectively, the
"Commitment Funds") pursuant to a Participation Letter Agreement executed as of
April 7, 2004, and that pursuant to such agreement the Commitment funds shall be
applied as a credit against the purchase price of the shares at the Closing.

      c. The first sentence of Section 3.3 is hereby restated to substitute
"15,225,757" for "15,100,757".

      d. The second sentence of Section 3.3 is hereby deleted in its entirety.

      e. A new Section 6.5 is hereby added to Article VI to read as follows:
"All parties shall have executed an Assignment of Working Interest in Initial
Well in substantially the form attached hereto as Exhibit E.



      f. A new Exhibit E is hereby added to the Agreement in the form attached
hereto as Exhibit A.

      g. A new Section 7.15 is hereby added to Article VII to read as follows:
"The Company and LLC shall have executed an Amendment to this Agreement
restating the number of shares to be issued to Buyer and modifying certain other
provisions.

      h. A new Section 7.16 is hereby added to Article VII to read as follows:
"Buyer shall have received a fully-executed Amendment No. 1 to the employment
agreement of Alan Gaines in substantially the form attached hereto as Exhibit F.

      i. A new Exhibit F is hereby added to the Agreement in the form attached
hereto as Exhibit B.

      j. A new Section 7.17 is hereby added to Article VII to read as follows:
"Buyer shall have received copies of the resolutions approving the transactions
contemplated in this Agreement as adopted by all of the Company's Board of
Directors, as well as copies of the minutes of the Board of Directors' meeting
at which the transactions were approved."

      k. A new Section 7.18 is hereby added to Article VII to read as follows:
"The Company and LLC shall have executed an Escrow Agreement in substantially
the form attached hereto as Exhibit G."

      l. A new Exhibit G is hereby added to the Agreement in the form attached
hereto as Exhibit C.

      m. A new Section 7.19 is hereby added to Article VII to read as follows:
"Buyer shall have received a fully-executed agreement relating to the issuance
of additional shares to Buyer in the event of any subsequently-discovered
discrepancies in the representations in this Agreement relating to the
capitalization of the Company and Schedule 3.3 in substantially the form
attached hereto as Exhibit H."

      n. A new Exhibit H is hereby added to the Agreement in the form attached
hereto as Exhibit D.

      o. A new Section 7.20 is hereby added to Article VII to read as follows:
"All of the parties shall have executed an Escrow Agreement in substantially the
form attached hereto as Exhibit I."

      p. A new Exhibit I is hereby added to the Agreement in the form attached
hereto as Exhibit E.

      q. A new Section 7.21 is hereby added to Article VII to read as follows:
"Buyer shall have received written notice from Company regarding the amount of
actual costs associated with the drilling and completion of the Initial Well (as
defined in that certain Participation Letter Agreement entered into among the
parties hereto and dated April 7, 2004 (the "PLA") that are set forth in the
Authorization for Expenditure and that exceed $850,000 as contemplated in
paragraph 5 of the Participation Letter Agreement dated April 7, 2004."


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      r. The first bullet point of Schedule 3.3 is hereby deleted in its
entirety.

      s. The third bullet point of Schedule 3.3 is hereby restated to substitute
"2,974,377" for "2,854,377."

      t. The following bullet point is hereby added to Schedule 3.3: "Chris
Lautenslager has been granted "piggy-back" registration rights with respect to
125,000 shares of Common Stock."

      u. The first sentence of paragraph #17 of Exhibit B is hereby restated to
substitute "15,225,757" where "15,100,757" appears, and the last sentence of
such paragraph is hereby restated to substitute "2,974,377" for "2,854,377."

      4. Controlling Agreement. To the extent any provisions contained herein
conflict with the Agreement or any other agreements between Seller, Buyer and
LLC, oral or otherwise, the provisions contained herein shall supersede such
conflicting provisions contained in the Agreement or other agreements. Except as
modified herein, Seller, Buyer and LLC hereby represent and warrant that the
Agreement remains in full force and effect and is hereby reaffirmed and ratified
by Seller, Buyer and LLC.

      5. Counterparts, Facsimiles. This Amendment may be executed in
counterparts. Each executed counterpart of this Amendment will constitute an
original document, and all executed counterparts, together, will constitute the
same agreement. Any counterpart evidencing signature by one party that is
delivered by telecopy by such party to the other party hereto shall be binding
on the sending party when such telecopy is sent, and such sending party shall
within the days thereafter deliver to the other parties a hard copy of such
executed counterpart containing the original signature of such party or its
authorized representative.

                         [SIGNATURES ON FOLLOWING PAGE]


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            IN WITNESS WHEREOF, the parties have executed this Amendment
effective the day and year first set forth above.


                                                     SELLER:

                                                     DUNE ENERGY, INC.

Date: May 17, 2004                                   By: /s/ Alan Gaines
                                                     Name: Alan Gaines
                                                     Its: Chairman and Chief
                                                          Executive Officer


                                                     LLC:

                                                     VAQUERO PARTNERS, LLC

Date: May 17, 2004                                   By: /s/ Alan Gaines
                                                     Name: Alan Gaines
                                                     Its: Manager


                                                     BUYER:

                                                     ITERA HOLDINGS B.V.

Date: May 17, 2004                                   By: /s/ Raissa Frenkel
                                                     Name: Raissa Frenkel
                                                     Its: Authorized Signatory


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