Exhibit 10.16 AMENDMENT TO THE LIMITED PARTNERSHIP AGREEMENT OF CSR - WAHA PARTNERS, L.P. DATED JUNE 27, 2002 JANUARY 15, 2003 AMENDMENT TO THE LIMITED PARTNERSHIP AGREEMENT OF CSR - WAHA PARTNERS, L.P. THIS AMENDMENT TO THE LIMITED PARTNERSHIP AGREEMENT is entered into effective January 15, 2003, by and among CSR, LLC (the "General Partner") and those persons listed as Limited Partners on Exhibit A attached hereto. This Amendment is made in accordance with ARTICLE VIII. "TRANSFER OF INTERESTS IN THE PARTNERSHIP" Section 8.3 "Limited Partners". 1. The Limited Partner admitted to the Partnership on June 27, 2002 has sold its ninety-nine (99%) percent limited partnership interest and has deliver a duly executed purchase agreement to the General Partner (the "Substitute Limited Partner"); 2. The General Partner has consented to the sale and transfer of the ninety-nine (99%) percent limited partnership interest to the Substituted Limited Partner as listed on Amended Exhibit A. The Admission of the Substituted Limited Partner and the effective date of this Amendment shall be the day and y ear first above written. GENERAL PARTNER: CSR, LLC By: ----------------------------------- Mark A. Bush, Managing Member LIMITED PARTNER: BPK RESOURCES, INC. By: ----------------------------------- John B. Connally, III AMENDED EXHIBIT A PARTNERS AS OF JANUARY 15, 2003 LIMITED CAPITAL PERCENTAGE PARTNERS CONTRIBUTION INTEREST - -------- ------------ -------- BPK Resources, Inc. $2,000,000 99.0% 5858 Westheimer Street Suite 709 Houston, Texas 77057 GENERAL PARTNER - --------------- CSR, LLC $4,000 1.0% 5858 Westheimer Street Suite 708 Houston, Texas 77057