AMENDMENT NO. 1 TO CONTRIBUTION AGREEMENT

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Exhibit 2.3

AMENDMENT NO. 1 TO
CONTRIBUTION AGREEMENT

        This AMENDMENT NO. 1 TO CONTRIBUTION AGREEMENT (this "Amendment") is dated as of September 12, 2006, and is made by and among HH GP Holding, LLC, an Oklahoma limited liability company ("Holding LLC"), Xxxxx Xxxxxx, an individual residing in Enid, Oklahoma ("Xx. Xxxxxx"), Equity Financial Services, Inc., an Oklahoma corporation ("Equity Financial"), Xxx Xxxxxx, an individual residing in Enid, Oklahoma ("Xx. Xxxxxx"), the Xxxxxx Xxxx DST Trust (the "DST Trust"), the Xxxxxx Xxxx HJ Trust (the "HJ Trust"), Continental Gas Holdings, Inc., a Delaware corporation ("Continental Holdings"), Xxxxxx Holdings GP, LP, a Delaware limited partnership ("HPGP"), Xxxxxx Partners GP, Inc., a Delaware corporation ("Xxxxxx Partners, Inc.") and Xxxxxx Partners GP Holdings, LLC, a Delaware limited liability company ("Holdings GP"). Holding LLC, Xx. Xxxxxx, Equity Financial, Xx. Xxxxxx, the DST Trust, the HJ Trust and Continental Holdings are sometimes referred to herein collectively as the "Existing Investors." Terms that are capitalized but not defined shall have the meanings assigned to such terms in the Contribution Agreement (as defined below).

RECITALS

        WHEREAS, the Existing Investors entered into that certain Contribution Agreement dated as of May 24, 2006 (the "Contribution Agreement"); and

        WHEREAS, the Existing Investors desire to execute this Amendment for purposes of clarifying a mistake in the definition of Total Existing Investors Value.

        NOW, THEREFORE, the defined term Total Existing Investors Value contained in Article I is hereby amended to read in its entirety as follows:

        "Total Existing Investors Value" means the total number of HPGP Units outstanding upon completion of the HPGP Initial Public Offering multiplied by the Initial Public Offering Price.

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        IN WITNESS WHEREOF, the parties to this Amendment No. 1 to the Contribution Agreement have caused it to be duly executed as of September 12, 2006.

		HH GP HOLDING, LLC
		By:		/s/  XXXXXX XXXX
		Name:		Xxxxxx Xxxx
		Title:		Sole Member
		/s/  XXXXX XXXXXX Xxxxx Xxxxxx
		/s/  XXXXXXXX X. XXXXXX Xxxxxxxx X. Xxxxxx
		EQUITY FINANCIAL SERVICES, INC.
		By:		/s/  XXXXX XXXXXX
		Name:		Xxxxx Xxxxxx
		Title:		President
		/s/  XXX XXXXXX Xxx Xxxxxx
		/s/  XXXX X. XXXXXX Xxxx X. Xxxxxx
		XXXXXX XXXX DST TRUST
		By:		/s/  XXXX XXXXXX
		Name:		Xxxx Xxxxxx
		Title:		Trustee
		XXXXXX XXXX HJ TRUST
		By:		/s/  XXXX XXXXXX
		Name:		Xxxx Xxxxxx
		Title:		Trustee

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		CONTINENTAL GAS HOLDINGS, INC.
		By:		/s/  XXXXXX XXXX
		Name:		Xxxxxx Xxxx
		Title:		Chief Executive Officer and Director
		XXXXXX HOLDINGS GP, LP
		By:		Xxxxxx Partners GP Holdings, LLC
		By:		/s/  XXXXX XXXXXX
		Name:		Xxxxx Xxxxxx
		Title:		President and Chief Executive Officer
		XXXXXX PARTNERS GP HOLDINGS, LLC
		By:		/s/  XXXXX XXXXXX
		Name:		Xxxxx Xxxxxx
		Title:		President and Chief Executive Officer
		XXXXXX PARTNERS GP, INC.
		By:		/s/  XXXXX XXXXXX
		Name:		Xxxxx Xxxxxx
		Title:		President and Chief Executive Officer

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AMENDMENT NO. 1 TO CONTRIBUTION AGREEMENT