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                                                                     Exhibit 3.6



                       AMENDED CERTIFICATE OF DESIGNATION
                                       OF
                     SERIES A PARTICIPATING PREFERRED STOCK
                                       OF
                               CALPINE CORPORATION

                         (PURSUANT TO SECTION 151 OF THE
                        DELAWARE GENERAL CORPORATION LAW)
                            ------------------------


     CALPINE CORPORATION, a corporation organized and existing under the General
Corporation Law of the State of Delaware (the "Company"), in accordance with the
provisions of Section 103 of the General Corporation Law of the State of
Delaware, certifies as follows:

     1. That by resolution of the Board of Directors of the Company dated June
5, 1997, and by a Certificate of Designation filed in the office of the
Secretary of State of the State of Delaware on June 16, 1997, as thereafter
amended by an Amended Certificate of Designation filed in the office of the
Secretary of State of the State of Delaware on March 2, 2001, the Company
authorized a series of shares of Series A Participating Preferred Stock, par
value $0.001 per share, of the Company (the "Series A Preferred Stock") and
established the powers, designations, preferences and relative, participating,
optional and other rights of the Series A Preferred Stock and the
qualifications, limitations or restrictions thereof.

     2. As of the date hereof, no shares of Series A Preferred Stock are
outstanding and no shares of Series A Preferred Stock have been issued.

     3. The pursuant to the authority conferred on the Board of Directors of the
Company by its Restated Certificate of Incorporation and the provisions of
Section 151(g) of the General Corporation Law of the State of Delaware, the
Board of Directors on July 25, 2001, adopted the following resolution amending
certain provisions of said Certificate of Designation:

          RESOLVED FURTHER, that the Board finds it advisable to amend the
     Certificate of Designation of Series A Participating Preferred Stock of
     Calpine Corporation (as amended on March 2, 2001, the "Series A Preferred
     Certificate of Designation"), and the Series A Preferred Certificate of
     Designation is hereby amended, as follows: the phrase "Five Hundred
     Thousand (500,000)" in the first sentence of Section 1 of the Series A
     Preferred Certificate of Designation is deleted and replaced with the
     phrase "One Million (1,000,000)".



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     IN WITNESS WHEREOF, CALPINE CORPORATION has caused this certificate to be
executed by Ann B. Curtis, the Executive Vice President, Chief Financial Officer
and Secretary of the Company, this 25th day of July, 2001.

                                           /s/  Ann B. Curtis
                                       ------------------------------
                                       Ann B. Curtis
                                       Executive Vice President, Chief Financial
                                         Officer and Secretary


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