<PAGE>   1


                                                                     EXHIBIT 4.2


        REGISTRATION RIGHTS AGREEMENT, dated as of April 13, 2001, among
        Calpine Corporation, a Delaware corporation (the "Company"), and
        the parties listed on Schedule I attached hereto (the
        "Stockholders")



                                  INTRODUCTION

        The Company, WRMS Engineering, Inc. and the Stockholders have entered
into a Share Purchase Agreement, dated as of April 3, 2001 (the "Purchase
Agreement"), pursuant to which, among other things, the Company is issuing, and
the Stockholders are acquiring, shares of the Company's common stock, par value
$0.001 per share (the "Common Stock").

        The execution and delivery of this Agreement by the Company and the
Stockholders is a condition precedent to the obligations of the Stockholders
under the Purchase Agreement.

        Capitalized terms used herein without definition shall have the meanings
given to them in Section 9(b).

        In consideration of the foregoing, the covenants and obligations set
forth below and other good and valuable consideration, the parties agree as
follows:

        1. Registration. Subject to the terms and conditions of this Agreement,
the Company shall cause the Registrable Securities to be registered for public
resale within the United States by the Stockholders.

        2. Registration Procedures. The Company shall, at its expense, as
expeditiously as possible:

        (a) within five (5) days after the Closing Date, subject to the
provisions of Section 8, prepare and file with the Securities and Exchange
Commission (the "Commission") a registration statement on Form S-3 or other
available form (as may be amended or supplemented from time to time, the
"Registration Statement"), relating to the public resale of the Registrable
Securities. The Company shall use commercially reasonable efforts to cause the
Registration Statement to be declared effective by the Commission. The
Registration Statement shall include a prospectus (as may be amended or
supplemented from time to time, the "Prospectus") to be delivered by each Holder
to the purchaser of his, her or its Registrable Securities;

        (b) subject to the provisions of Section 8, prepare and file with the
Commission such amendments and supplements to the Registration Statement and the
Prospectus as may be necessary to keep the Registration Statement effective, and
the Prospectus current, for one year from the Closing Date, unless prior to the
expiration of such period all of the Registrable Securities have been sold;

<PAGE>   2

        (c) furnish to each Holder such number of copies of the Registration
Statement and/or the Prospectus as may be required pursuant to the Securities
Act of 1933, as amended (the "Securities Act"), or as a Holder may reasonably
request; and

        (d) use its best efforts to list the Registrable Securities on the New
York Stock Exchange or, if the Common Stock is de-listed from such exchange, the
securities exchange or interdealer quotation system on which the Common Stock is
subsequently listed or quoted, if such listing is then permitted under the rules
of such exchange or system.

        3. Expenses. All expenses incurred in connection with the Registration
Statement, the Prospectus and the other undertakings of the Company pursuant to
this Agreement shall be borne by the Company; provided, however, that the
Company shall not be responsible for any underwriting discounts, selling
commissions or fees, stock transfer taxes or similar costs, incurred in
connection with a Holder's sale of Registrable Securities.

        4. Indemnification and Contribution.

        (a) Indemnification by the Company. The Company, to the extent permitted
by applicable law, will indemnify and hold harmless each Holder of Registrable
Securities included in the Registration Statement pursuant to the provisions of
this Agreement and each other person, if any, who controls such Holder within
the meaning of Section 15 of the Securities Act (a "Holder Indemnified Party")
and will reimburse each Holder Indemnified Party with respect to, any and all
claims, actions, demands, losses, damages, liabilities, costs and expenses,
including the reasonable fees and expenses of legal counsel (collectively,
"Claims"), to which such Holder Indemnified Party becomes subject, insofar as
such Claims arise out of or are based upon (i) any untrue statement (or alleged
untrue statement) of any material fact contained in the Registration Statement
or the Prospectus, or (ii) any omission (or alleged omission) to state in the
Registration Statement or Prospectus a material fact required to be stated
therein or necessary to make the statements therein not misleading, or (iii) any
violation by the Company of any rule or regulation under the Securities Act or
any state securities laws applicable to the Company and relating to action or
inaction required of the Company in connection with such registration; provided,
however, that the Company will not be liable in any case to the extent that any
Claim arises out of or is based upon an untrue statement (or alleged untrue
statement) or omission (or alleged omission) so made in reliance upon
information furnished to the Company by a Holder. This indemnity shall remain in
full force and effect regardless of any investigation made by or on behalf of a
Holder Indemnified Party.

        (b) Indemnification by the Holders. Each Holder of shares of Registrable
Securities, severally and not jointly, to the extent permitted by law, will
indemnify and hold harmless the Company, each other person, if any, who controls
the Company within the meaning of Section 15 of the Securities Act, each officer
of the Company who signs the Registration Statement and each director of the
Company (collectively, the "Company Indemnified Parties") from and against, and
will reimburse each Company Indemnified Party with respect to, any and all
Claims to which such Company Indemnified Party becomes subject, insofar as such
Claims arise out of or are based upon (i) any untrue statement (or alleged
untrue statement) of any material fact contained in the Registration Statement
or the Prospectus, or (ii) any omission (or alleged omission) to state in the
Registration Statement or Prospectus a material fact required to be stated
therein or necessary to make the statements therein not misleading, or (iii) any
violation


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<PAGE>   3

by the Holder of any rule or regulation under the Securities Act or any state
securities laws applicable to the Holder and relating to action or inaction
required of the Holder in connection with such registration; provided, however,
that each Holder will be liable to the Company Indemnified Parties only to the
extent that the Claims arise out of or are based upon an untrue statement (or
alleged untrue statement) or omission (or alleged omission) made in reliance
upon information furnished by such Holder for use in the preparation of the
Registration Statement or the Prospectus. This indemnity shall remain in full
force and effect regardless of any investigation made by or on behalf of a
Company Indemnified Party.

        (c) Notices of Claims, etc. Promptly after receipt by a person to be
indemnified pursuant to the provisions of Section 4(a) or (b) (an "indemnified
party") of notice of the commencement of any action involving the subject matter
of the foregoing indemnity provisions, such indemnified party will, if a claim
thereof is to be made against the indemnifying party pursuant to the provisions
of this Section 4(a) or (b), notify the indemnifying party of the commencement
thereof, but the omission to so notify the indemnifying party will not relieve
it from any liability which it may have to an indemnified party otherwise than
under this Section 4 and shall not relieve the indemnifying party from liability
under this Section 4 unless such indemnifying party is prejudiced by such
omission. In case such action is brought against any indemnified party and it
notifies the indemnifying party of the commencement thereof, the indemnifying
party shall have the right to participate in, and, to the extent that it may
wish, jointly with any other indemnifying party similarly notified, to assume
the defense thereof, with counsel reasonably satisfactory to such indemnified
party, and after the notice from the indemnifying party to such indemnified
party of its election to assume the defense thereof, the indemnifying party will
not be liable to such indemnified party pursuant to the provisions of Section
4(a) and (b) for any legal expense subsequently incurred by such indemnified
party in connection with the defense thereof other than reasonable costs of
investigation; provided, however, that, if the defendants in any such action
include both the indemnified party and the indemnifying party and the
indemnified party shall have reasonably concluded that there may be reasonable
defenses available to it that are different from or additional to those
available to the indemnifying party or if the interests of the indemnified party
reasonably may be deemed to conflict with the interests of the indemnifying
party, the indemnified party shall have the right to select a separate counsel
and to assume such legal defenses and otherwise to participate in the defense of
such action, with the expenses and fees of such separate counsel and other
expenses related to such participation to be reimbursed by the indemnifying
party as incurred; provided, further, that the indemnifying party shall be
required to pay the fees of only one separate counsel for all indemnified
parties in such action. No indemnifying party shall be liable to an indemnified
party for any settlement of any action or claim without the consent of the
indemnifying party, and no indemnifying party may unreasonably withhold its
consent to any such settlement. No indemnifying party will, except with the
consent of the indemnified party, consent to entry of any judgment or enter into
any settlement which does not include as an unconditional term thereof the
giving by the claimant or plaintiff to such indemnified party of a release from
all liability in respect to such claim or litigation.

        (d) Contribution. In order to provide for just and equitable
contribution to joint liability under the Securities Act in any case in which
either (i) any Holder Indemnified Party exercising rights under this Agreement
makes a claim for indemnification pursuant to this Section 4 but it is
judicially determined (by the entry of a final judgment or decree by a court of


                                      -3-
<PAGE>   4

competent jurisdiction and the expiration of time to appeal or the denial of the
last right of appeal) that such indemnification may not be enforced in such case
notwithstanding the fact that this Section 4 provides for indemnification in
such case, or (ii) contribution under the Securities Act may be required on the
part of any such Holder Indemnified Party in circumstances for which
indemnification is provided under this Section 4, then, and in each such case,
the Company and such Holder will contribute to the aggregate losses, claims,
damages or liabilities to which they may be subject (after contribution from
others) in such proportion as is appropriate to reflect the relative fault of
the Company on the one hand and of the Holder on the other in connection with
the statements or omissions that resulted in such losses, claims, damages or
liabilities, as well as any other relevant equitable considerations. The
relative fault of the Company on the one hand and of the Holder on the other
shall be determined by reference to, among other things, whether the untrue or
alleged untrue statement of a material fact or omission or alleged omission to
state a material fact relates to information supplied by the Company on the one
hand or by the Holder of Registrable Securities on the other, and each party's
relative intent, knowledge, access to information and opportunity to correct or
prevent such statement or omission; provided, however, that, in any such case,
no person or entity guilty of fraudulent misrepresentation (within the meaning
of Section 11(f) of the Securities Act) will be entitled to contribution from
any person or entity who was not guilty of such fraudulent misrepresentation.

        5. Reporting Requirements.

        (a) Exchange Act Reporting. Until such time as all of the Registrable
Securities have been sold, the Company shall timely file with the Commission
such documents and reports as it may be required to file pursuant to Section
13(a), 14 or 15 of the Securities Exchange Act of 1934 (the "Exchange Act").

        (b) Furnishing Information to Holders. The Company shall promptly
furnish any Holder, upon request, with (i) a copy of the most recent annual
report of the Company and any subsequent quarterly and periodic reports of the
Company, and (ii) such other reports and documents filed by the Company with the
Commission as such Holder may reasonably request in availing itself of an
exemption for the sale of Registrable Securities without registration under the
Securities Act.

        6. Holder Information. As a condition to the performance of the
Company's obligations hereunder, each Holder of Registrable Securities shall
furnish to the Company, in a timely manner, such information with respect to the
Holder and the Holder's intended distribution of his, her or its Registrable
Securities as the Company may from time to time reasonably request and as shall
be required by law or by the rules and regulations of the Commission in
connection with the registration of the Registrable Securities owned by such
Holder.

        7. Restrictions on Transfer.

        (a) No Holder shall, directly or indirectly, sell, transfer, exchange,
assign, pledge, hypothecate, give or otherwise dispose of (including by means of
short sales, forward sales or equity derivative or other hedging or monetization
transactions) any Registrable Securities, or any right or interest therein, or
enter into any contract in respect of any of the foregoing, unless and until
such Registrable Securities are registered pursuant to Section 1;


                                      -4-
<PAGE>   5

provided, however, that, subject to the provisions relating to transfer
contained in the Purchase Agreement:

        (i) a Stockholder may transfer Registrable Securities without
        registration by gift to any member of the Stockholder's immediate family
        or to a trust solely for the benefit of the Stockholder and/or one or
        more members of such Stockholder's immediate family;

        (ii) Registrable Securities may be transferred without registration to a
        Holder's executor, administrator, trustee, or personal representative at
        death or involuntarily by operation of law; and

        (iii) Registrable Securities may be transferred without registration;
        provided, however, that as a condition precedent to each such sale, the
        Company shall have received an opinion of counsel to such selling
        Holder, such opinion to be in form and substance reasonably satisfactory
        to the Company, that such sale is exempt from registration under the
        Securities Act and all applicable state securities laws;

and in each case it shall be a condition to any such transfer that the
transferee agrees in a writing delivered to the Company to be bound by all of
the terms and conditions of this Agreement and that any such transfer otherwise
shall be exempt from registration under the Securities Act and all applicable
state securities laws.

        (b) Each stock certificate representing Registrable Securities shall be
imprinted with the following legend:

        THE SHARES REPRESENTED BY THIS CERTIFICATE HAVE NOT BEEN
        REGISTERED UNDER THE SECURITIES ACT OF 1933 OR ANY STATE
        SECURITIES LAWS. SUCH SHARES MAY NOT BE PLEDGED, OFFERED, SOLD
        OR TRANSFERRED EXCEPT IN COMPLIANCE WITH THE REGISTRATION
        REQUIREMENTS OF THE SECURITIES ACT OF 1933, AS AMENDED, AND
        APPLICABLE STATE SECURITIES LAWS OR UNLESS AN EXEMPTION FROM
        SUCH REGISTRATION REQUIREMENTS IS AVAILABLE AND UPON DELIVERY TO
        THE COMPANY, IF REQUESTED, OF AN OPINION OF COUNSEL IN FORM AND
        SUBSTANCE REASONABLY SATISFACTORY TO THE COMPANY THAT
        REGISTRATION IS NOT REQUIRED. THE SHARES REPRESENTED BY THIS
        CERTIFICATE ARE HELD SUBJECT TO THE TERMS OF A REGISTRATION
        RIGHTS AGREEMENT, DATED AS OF APRIL [ ], 2001. A COPY OF THE
        REGISTRATION RIGHTS AGREEMENT IS AVAILABLE FOR INSPECTION DURING
        NORMAL BUSINESS HOURS AT THE PRINCIPAL OFFICES OF THE COMPANY.
        NEITHER THIS CERTIFICATE NOR THE SHARES REPRESENTED


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<PAGE>   6

        HEREBY MAY BE SOLD, ASSIGNED, TRANSFERRED, MORTGAGED, PLEDGED,
        HYPOTHECATED, OR OTHERWISE DISPOSED OR ENCUMBERED, DIRECTLY OR
        INDIRECTLY, EXCEPT IN ACCORDANCE WITH THE PROVISIONS OF SUCH
        REGISTRATION RIGHTS AGREEMENT.

The Company may instruct its transfer agent to impose appropriate stop transfer
procedures to enforce the restrictions imposed by Section 7(a).

        (c) The legend specified in Section 7(b) shall be removed and the
Company shall promptly issue, or shall promptly cause to be issued, a
certificate without such legend to the Holder of any Registrable Securities in
conjunction with any resale of such Registrable Securities effected pursuant to
the Registration Statement and the Prospectus, provided that such resale is made
in accordance with the terms of this Agreement.

        8. Suspension of the Company's Obligations.

        (a) Notwithstanding any other provision in this Agreement to the
contrary, the Company's obligations to file the Registration Statement, cause
the Registration Statement to remain effective and/or keep the Prospectus
current shall be suspended (a "Suspension") if the Company shall furnish to the
Holders a certificate signed by a senior officer of the Company (a "Suspension
Certificate") stating that in the reasonable judgment of the Company it would be
detrimental to the Company and its stockholders for the Company to take the
actions necessary to fulfill such obligations at such time due to undisclosed
pending Company events. Any such Suspension shall terminate twenty-four (24)
hours after disclosure of such events by the Company or the termination of such
events, in either case as evidenced by a certificate of the Company furnished to
the Holders. Each Holder, by executing and delivering a copy of this Agreement,
shall be deemed (i) to have acknowledged that the receipt of a Suspension
Certificate shall constitute the receipt of material nonpublic information
regarding the Company and (ii) to have expressly agreed to maintain such
information in confidence and to abstain from directly or indirectly selling,
transferring, exchanging, assigning, pledging, hypothecating, giving or
otherwise disposing of any Registrable Securities or any right or interest
therein, or any other Company securities, until such time as the Holders have
been advised in writing by the Company that such event has been disclosed or
terminated as described above.

        (b) In the event that a Suspension shall be in effect for more than 120
continuous days, the Company shall pay to each Holder an amount, in cash, per
Registrable Security held by the Holder as of the end of the Suspension equal to
one--half (_) of the positive difference, if any, between the average of the
closing prices of the Common Stock on the New York Stock Exchange (or such other
stock exchange or interdealer quotation as may then be the primary U.S. trading
market for the Common Stock) (the "Average Price") for the first twenty (20)
trading days of the Suspension and the Average Price for the last twenty (20)
days of the Suspension.


                                      -6-
<PAGE>   7

        9. Descriptive Headings; Definitions; Certain Interpretations.

        (a) Descriptive headings are for convenience only and shall not control
or affect the meaning or construction of any provision of this Agreement.

        (b) As used in this Agreement, the following terms shall have the
following respective meanings:

        "Affiliate" means (a) any person directly or indirectly controlling,
controlled by or under common control with another person; (b) any person owning
or controlling 10% or more of the outstanding voting securities of such other
person; (c) any partner, officer, director, employee or stockholder of such
person or any parent, spouse, child, brother, sister or other relative with a
relationship (by blood, marriage or adoption) or not more remote than first
cousin of any of the foregoing; or (d) any liquidating trust, trustee or other
similar person or entity for any person.

        "Holder" means (a) any Stockholder and (b) any other person to which the
rights of registration under this Agreement have been transferred or assigned by
a Stockholder in accordance with the terms of this Agreement.

        "Registrable Securities" means (a) the [ ] shares of Common Stock issued
to the Stockholders pursuant to the Purchase Agreement and (b) any shares of
Common Stock issued in respect of such shares by way of a stock dividend or
stock split or in connection with a combination of shares, recapitalization,
merger or consolidation or reorganization; provided, however, that any such
shares shall cease to be Registrable Securities when such securities have been
sold in a public distribution or a public securities transaction or become
eligible for resale pursuant to the provisions of Rule 144 under the Securities
Act (or any similar or successor exemptive provision hereafter in effect).

        "Registration Expenses" means any and all expenses incident to
performance of or compliance with this Agreement, including (i) all filing fees
of the Commission, (ii) all fees and expenses of complying with state securities
or blue sky laws, (iii) all printing, messenger and delivery expenses, (iv) all
fees and expenses incurred in connection with the listing of the Registrable
Securities on any securities exchange pursuant to Section 2(g), and (v) the fees
and disbursements of counsel for the Company and of its independent public
accountants.

        (c) Except as otherwise expressly provided in this Agreement, the
following rules of interpretation apply to this Agreement: (i) the singular
includes the plural and the plural includes the singular; (ii) "or" or "any" are
not exclusive and "include" and "including" are not limiting; (iii) a reference
to any agreement or other contract includes permitted supplements and
amendments; (iv) a reference to a law includes any amendment or modification to
such law and any rules or regulations issued thereunder; (v) a reference to a
person includes its permitted successors and assigns; and (vi) a reference in
this Agreement to a Section is to the Section of this Agreement.

        10. Notices. All notices, requests and other communications to any party
hereunder shall be in writing and sufficient if delivered personally or sent by
telecopy (with


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<PAGE>   8

confirmation of receipt) or by registered or certified mail, postage prepaid,
return receipt requested, addressed as follows:

        If to the Company:               Calpine Corporation
                                         50 West San Fernando Street
                                         San Jose, California 95113
                                         Attention:  Ann B. Curtis
                                         Fax No.:  (408) 995-0505

        With a copy to:                  Covington & Burling
                                         1330 Avenue of the Americas
                                         New York, New York 10019
                                         Attention:  Bruce C. Bennett
                                         Fax No.:  (212) 841-1010

If to any Stockholder, to its address as provided on the signature pages hereto,
or to such other address or telecopy number as the party to whom notice is to be
given may have furnished to the other party in writing in accordance herewith.
Each such notice, request or communication shall be effective when received or,
if given by mail, when delivered at the address specified in this Section or on
the fifth business day following the date on which such communication is posted,
whichever occurs first.

        11. Counterparts. This Agreement may be executed in any number of
counterparts, and each such counterpart hereof shall be deemed to be an original
instrument, but all such counterparts together shall constitute but one
agreement.

        12. Benefits of Agreement. All of the terms and provisions of this
Agreement shall be binding upon and inure to the benefit of the parties hereto
and their respective successors and permitted assigns. This Agreement is for the
sole benefit of the parties hereto and not for the benefit of any third party.

        13. Enforceability. It is the desire and intent of the parties hereto
that the provisions of this Agreement shall be enforced to the fullest extent
permissible under the laws and public policies applied in each jurisdiction in
which enforcement is sought. Accordingly, if any particular provision of this
Agreement shall be adjudicated to be invalid or unenforceable, such provision
shall be deemed amended to delete therefrom the portion thus adjudicated to be
invalid or unenforceable, such deletion to apply only with respect to the
operation of such provision in the particular jurisdiction in which such
adjudication is made.

        14. GOVERNING LAW. THIS AGREEMENT SHALL BE GOVERNED BY AND CONSTRUED IN
ACCORDANCE WITH THE LAWS OF THE STATE OF NEW YORK (WITHOUT GIVING EFFECT TO ANY
CHOICE OR CONFLICT OF LAWS PROVISIONS).

        15. WAIVER OF JURY TRIAL. EACH PARTY HERETO HEREBY WAIVES, TO THE
FULLEST EXTENT PERMITTED BY APPLICABLE LAW, ANY RIGHT IT MAY HAVE TO A TRIAL BY
JURY IN RESPECT OF ANY LITIGATION DIRECTLY OR INDIRECTLY ARISING OUT OF, UNDER
OR IN CONNECTION


                                      -8-
<PAGE>   9

WITH THIS AGREEMENT. EACH PARTY HERETO (A) CERTIFIES THAT NO REPRESENTATIVE,
AGENT OR ATTORNEY OF THE OTHER PARTY HAS REPRESENTED, EXPRESSLY OR OTHERWISE,
THAT THE OTHER PARTY WOULD NOT, IN THE EVENT OF LITIGATION, SEEK TO ENFORCE THE
FOREGOING WAIVER AND (B) ACKNOWLEDGES THAT IT AND THE OTHER PARTY HERETO HAVE
BEEN INDUCED TO ENTER INTO THIS AGREEMENT, BY, AMONG OTHER THINGS, THE MUTUAL
WAIVERS AND CERTIFICATIONS IN THIS SECTION 15.

        16. Successors and Assigns. This Agreement shall be binding upon and
shall inure to the benefit of the parties hereto and their respective successors
and permitted assigns. The Stockholders' rights hereunder may not be assigned to
any person or entity except a transferee of Registrable Securities pursuant to
an unregistered transfer by a Stockholder in accordance with the proviso set
forth in Section 7(a).

        17. Entire Agreement. This Agreement contains the entire agreement and
understanding between the parties hereto with respect to the registration of the
Registrable Securities by the Company under the Securities Act and supersedes
all prior agreements with respect to its subject matter and understandings,
written or oral, among the parties with respect to the subject matter hereof.

        18. Amendment and Waiver. This Agreement and the rights granted to the
Stockholders may be modified, amended or waived only by a writing signed by each
party hereto.

        IN WITNESS WHEREOF, the parties have duly executed this Agreement as of
the date first above written.

                                            CALPINE CORPORATION



                                            By: /s/ E.J. MACIAS
                                               ---------------------------------
                                               Name:      E.J. Macias
                                               Title:     Senior Vice President


                                      -9-
<PAGE>   10

                              HOLDER SIGNATURE PAGE





                                             -----------------------------------
                                             Print Name of Holder




                                             -----------------------------------
                                             Signature




                                             -----------------------------------
                                             Print Name of Signatory (if Holder
                                             is not a natural person)




                                             -----------------------------------
                                             Title of Signatory (if Holder is
                                             not a natural person)



                                             Address:


                                             -----------------------------------

                                             -----------------------------------

                                             -----------------------------------

                                             -----------------------------------



                                      -10-
<PAGE>   11

                              HOLDER SIGNATURE PAGE





                                             David W. Winn
                                             -----------------------------------
                                             Print Name of Holder



                                             /s/ DAVID W. WINN
                                             -----------------------------------
                                             Signature




                                             -----------------------------------
                                             Print Name of Signatory (if Holder
                                             is not a natural person)




                                             -----------------------------------
                                             Title of Signatory (if Holder is
                                             not a natural person)



                                             Address:


                                             3400 Echo Springs Road
                                             Lafayette, CA  94549



<PAGE>   12


                              HOLDER SIGNATURE PAGE




                                             Michael Rojansky
                                             -----------------------------------
                                             Print Name of Holder



                                             /s/ MICHAEL ROJANSKY
                                             -----------------------------------
                                             Signature




                                             -----------------------------------
                                             Print Name of Signatory (if Holder
                                             is not a natural person)




                                             -----------------------------------
                                             Title of Signatory (if Holder is
                                             not a natural person)



                                             Address:


                                             109 La Sonoma Way
                                             Alamo, CA  94507


<PAGE>   13


                              HOLDER SIGNATURE PAGE




                                             Patrick Ryan
                                             -----------------------------------
                                             Print Name of Holder



                                             /s/ PATRICK RYAN
                                             -----------------------------------
                                             Signature




                                             -----------------------------------
                                             Print Name of Signatory (if Holder
                                             is not a natural person)




                                             -----------------------------------
                                             Title of Signatory (if Holder is
                                             not a natural person)



                                             Address:


                                             70 St. Luke Court
                                             Danville, CA  94526


<PAGE>   14


                              HOLDER SIGNATURE PAGE




                                             James R. Rowland
                                             -----------------------------------
                                             Print Name of Holder




                                             Signature



                                             /s/ JAMES R. ROWLAND
                                             -----------------------------------
                                             Print Name of Signatory (if Holder
                                             is not a natural person)




                                             -----------------------------------
                                             Title of Signatory (if Holder is
                                             not a natural person)



                                             Address:


                                            21 Avis Road
                                            Berkeley, CA  94707


<PAGE>   15


                                   SCHEDULE I


                                   David Winn
                                Michael Rojansky
                                  Patrick Ryan
                                James R. Rowland