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                     FIRST AMENDMENT TO GUARANTEE AGREEMENT

                          Dated as of October 18, 2001

                                     Between

                              CALPINE CORPORATION,

                                  AS GUARANTOR

                                       and

                            WILMINGTON TRUST COMPANY,

                                   AS TRUSTEE

                        Amending the Guarantee Agreement

                          Dated as of October 18, 2001



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                This FIRST AMENDMENT TO GUARANTEE AGREEMENT, dated as of October
18, 2001 (the "First Amendment"), is between Calpine Corporation, a Delaware
corporation, as guarantor (the "Guarantor"), and Wilmington Trust Company, a
Delaware banking corporation, as trustee under the Indenture referred to below
("the Trustee").

                WHEREAS, the Guarantor executed and delivered the Guarantee
Agreement dated as of October 18, 2001 (the "Guarantee Agreement") to the
Trustee, which guarantees Securities (as defined below) issued under the
Indenture dated as of October 18, 2001 (the "Indenture") between Calpine Canada
Energy Finance II ULC, an unlimited liability company organized under the laws
of Nova Scotia, Canada (the "Company"), and the Trustee, as provided in the
Guarantee Agreement;

                WHEREAS, simultaneously with the execution of this First
Amendment, the Company is issuing Pound Sterling200,000,000 8-7/8% Senior Notes
Due October 15, 2011 (the "Sterling 8-7/8% Notes") and E175,000,000 8-3/8%
Senior Notes Due October 15, 2008 (the "Euro 8-3/8% Notes") pursuant to the
Indenture and the Guarantor is guaranteeing each Sterling 8-7/8% Note and each
Euro 8-3/8% Note pursuant to the Guarantee Agreement;

                WHEREAS, the Guarantor and the Trustee desire to amend the
Guarantee Agreement to add to the covenants of the Guarantor solely for the
benefit of the Holders (as defined below) of the Sterling 8-7/8% Notes and the
Holders of the Euro 8-3/8% Notes and to make related changes to the Guarantee
Agreement;

                WHEREAS, Section 4.01 of the Guarantee Agreement provides that
the Guarantee Agreement may be amended by the Guarantor and the Trustee without
notice to or the consent of any Securityholder (as defined below) for such
purpose provided certain conditions are met;

                WHEREAS, all things necessary to make this First Amendment a
valid agreement of the Guarantor and the Trustee, in accordance with its terms,
and a valid amendment of the Guarantee Agreement have been done.

                NOW THEREFORE, for and in consideration of the premises and
mutual covenants herein contained, the Guarantor and the Trustee agree as
follows:

                                    ARTICLE I

                                   DEFINITIONS

                Section 1.1 Definition of Terms.

                Unless the context otherwise requires:

                (a) capitalized terms used herein that are not otherwise defined
herein shall have the meaning assigned to such terms in the Guarantee Agreement;

                (b) the singular includes the plural and vice versa; and

                (c) headings are for convenience of reference only and do not
affect interpretation.



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                                   ARTICLE II
                      AMENDMENTS TO THE GUARANTEE AGREEMENT

                Section 2.1 Amendment.

                (a) Article V of the Guarantee Agreement is amended to add the
following new Section 5.06:

                SECTION 5.06. Performance by a Subsidiary of the Guarantor of
                Certain Covenants Under Term Debenture.

                Solely for the benefit of the Holders of Sterling 8-7/8% Notes
                and the Holders of Euro 8-3/8% Notes, the Guarantor shall cause
                Calpine Canada Resources Ltd., a wholly-owned subsidiary of the
                Guarantor, to comply in all respects with its obligations under
                Section 7.1 of the Term Debenture, dated August 23, 2001,
                between the Company and Calpine Canada Resources Ltd.

                (b) Article II of the Guarantee Agreement is amended to add the
following new Section 2.05:

                SECTION 2.05. Additional Amounts.

                Whenever in this Guarantee Agreement there is mentioned, in any
                context, the payment of, or the guarantee of the payment of, the
                principal of or any premium, interest or any other amounts on,
                or in respect of, any Security of any Series, such mention shall
                be deemed to include mention of the payment of any additional
                amounts provided by the terms of the Sterling 8-7/8% Notes or
                the Euro 8-3/8% Notes, as applicable, established pursuant to
                the Indenture to the extent that, in such context, additional
                amounts are, were or would be payable in respect thereof
                pursuant to such terms, and express mention of the payment of,
                or the guarantee of the payment of, additional amounts (if
                applicable) in any provision hereof shall not be construed as
                excluding the payment of, or the guarantee of the payment of,
                additional amounts in those provisions hereof where such express
                mention is not made.

                                   ARTICLE III
                                  MISCELLANEOUS

                Section 3.1 Ratification of Guarantee Agreement.

                The Guarantee Agreement, as supplemented by this First
Amendment, is in all respects ratified and confirmed and this First Amendment
shall be deemed part of the Guarantee Agreement in the manner and to the extent
herein and therein provided.

                Section 3.2 Governing Law.

                The laws of the State of New York govern this First Amendment,
without regard to the conflicts of laws rules thereof.


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                Section 3.3 Separability Clause.

                In case any provision in this First Amendment shall be invalid,
illegal or unenforceable, the validity, legality and enforceability of the
remaining provisions shall not in any way be affected or impaired thereby.

                Section 3.4 Duplicate Originals.

                The parties may sign any number of copies of this First
Amendment. One signed copy is enough to prove this First Amendment.

                Section 3.5 Effectiveness.

                This First Amendment shall be effective and binding when
executed by the Guarantor and the Trustee.

                Section 3.6 Trustee Not Responsible for Recitals.

                The recitals herein contained are made by the Guarantor and not
by the Trustee and the Trustee assumes no responsibility for the correctness
thereof. The Trustee makes no representation as to the validity or sufficiency
of this First Amendment.

                                      * * *



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                IN WITNESS WHEREOF, the parties hereto have caused this First
Amendment to be duly executed as of the day and year first above written.

                                            CALPINE CORPORATION,
                                            as Guarantor

                                            By:  /s/ ERIC PRYOR
                                                --------------------------------
                                                Eric Pryor
                                                Senior Vice President

Agreed and Accepted:

WILMINGTON TRUST COMPANY,
as Trustee under the Indenture

By:  /s/ BRUCE L. BISSON
    --------------------------------
    Name:
    Title: Vice President




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