<PAGE>

THIS WARRANT AND THE SHARES ISSUABLE HEREUNDER HAVE NOT BEEN REGISTERED UNDER
THE SECURITIES ACT OF 1933, AS AMENDED, AND MAY NOT BE SOLD, PLEDGED, OR
OTHERWISE TRANSFERRED WITHOUT AN EFFECTIVE REGISTRATION THEREOF UNDER SUCH ACT
OR PURSUANT TO RULE 144 OR AN OPINION OF COUNSEL REASONABLY SATISFACTORY TO THE
CORPORATION AND ITS COUNSEL, THAT SUCH REGISTRATION IS NOT REQUIRED.


                             WARRANT TO PURCHASE STOCK

Corporation: SONOMA SYSTEMS, A CALIFORNIA CORPORATION
Number of Shares: 21,978 (SUBJECT TO THE PROVISION SET BELOW)
Class of Stock: SERIES E PREFERRED
Initial Exercise Price: $3.64 PER SHARE (SUBJECT TO THE PROVISION SET BELOW)
Issue Date: NOVEMBER 29, 1999
Expiration Date: NOVEMBER 29, 2004

     THIS WARRANT CERTIFIES THAT, for the agreed upon value of $1.00 and for
other good and valuable consideration, SILICON VALLEY BANK ("Holder") is
entitled to purchase the number of fully paid and nonassessable shares of the
class of securities (the "Shares") of the corporation (the "Company") at the
initial exercise price per Share (the "Warrant Price") all as set forth above
and as adjusted pursuant to Article 2 of this Warrant, subject to the
provisions and upon the terms and conditions set forth in this Warrant.
Notwithstanding the foregoing, if the Company fails to either (i) receive
$7,000,000 of the Private Placement (as such term is described in the Amended
and Restated Loan and Security Agreement of every date between the Company
and Holder) on or before December 31, 1999, or (ii) close the Private
Placement on or before March 31, 2000, the Number of Shares shall be 36,199
and the Initial Exercise Price shall be $2.21 per Share.

ARTICLE 1. EXERCISE.

           1.1   METHOD OF EXERCISE.  Holder may exercise this Warrant by
delivering a duly executed Notice of Exercise in substantially the form attached
as Appendix 1 to the principal office of the Company. Unless Holder is
exercising the conversion right set forth in Section 1.2, Holder shall also
deliver to the Company a check for the aggregate Warrant Price for the Shares
being purchased.

           1.2   CONVERSION RIGHT.  In lieu of exercising this Warrant as
specified in Section 1.1, Holder may from time to time convert this Warrant, in
whole or in part, into a number of Shares determined by dividing (a) the
aggregate fair market value of the Shares or other securities otherwise issuable
upon exercise of this Warrant minus the aggregate Warrant Price of such Shares
by (b) the fair market value of one Share. The fair market value of the Shares
shall be determined pursuant to Section 1.4.

           1.3   INTENTIONALLY OMITTED

           1.4   FAIR MARKET VALUE.  If the Shares are traded in a public
market, the fair market value of the Shares shall be the closing price of the
Shares (or the closing price of the Company's stock into which the Shares are
convertible) reported for the business day immediately before Holder delivers
its Notice of Exercise to the Company. If the Shares are not traded in a public
market, the Board of Directors of the Company shall determine fair market value
in its reasonable good faith judgment. The foregoing notwithstanding, if Holder
advises the Board of Directors in writing that Holder disagrees with such
determination, then the Company and Holder shall promptly agree upon a reputable
investment banking firm to undertake such valuation. If the valuation of such
investment banking firm is greater than that determined by the Board of
Directors, then all fees and expenses of such investment banking firm shall be
paid by the Company. In all other circumstances, such fees and expenses shall be
paid by Holder.

<PAGE>


           1.5   DELIVERY OF CERTIFICATE AND NEW WARRANT.  Promptly after Holder
exercises or converts this Warrant, the Company shall deliver to Holder
certificates for the Shares acquired and, if this Warrant has not been fully
exercised or converted and has not expired, a new Warrant representing the
Shares not so acquired.

           1.6   REPLACEMENT OF WARRANTS. On receipt of evidence reasonably
satisfactory to the Company of the loss, theft, destruction or mutilation of
this Warrant and, in the case of loss, theft or destruction, on delivery of an
indemnity agreement reasonably satisfactory in form and amount to the Company
or, in the case of mutilation, on surrender and cancellation of this Warrant,
the Company shall execute and deliver, in lieu of this Warrant, a new warrant of
like tenor.

           1.7   REPURCHASE ON SALE, MERGER, OR CONSOLIDATION OF THE COMPANY.

                 1.7.1  "ACQUISITION".  For the purpose of this Warrant,
"Acquisition" means any sale, license, or other disposition of all or
substantially all of the assets of the Company, or any reorganization,
consolidation, or merger of the Company where the holders of the Company's
securities before the transaction beneficially own less than 50% of the
outstanding voting securities of the surviving entity after the transaction.

                 1.7.2.  ASSUMPTION OF WARRANT.  Upon the closing of any
Acquisition the successor entity shall assume the obligations of this Warrant,
and this Warrant shall be exercisable for the same securities, cash, and
property as would be payable for the Shares issuable upon exercise of the
unexercised portion of this Warrant as if such Shares were outstanding on the
record date for the Acquisition and subsequent closing. The Warrant Price shall
be adjusted accordingly.

ARTICLE 2. ADJUSTMENTS TO THE SHARES.

           2.1   STOCK DIVIDENDS, SPLITS, ETC.  If the Company (i) declares or
pays a dividend on its common stock (or the Shares if the Shares are securities
other than common stock) payable in common stock, or other securities, or (ii)
subdivides the outstanding common stock into a greater amount of common stock,
or, if the Shares are securities other than common stock, subdivides the Shares
in a transaction that increases the amount of common stock into which the Shares
are convertible, then upon exercise of this Warrant, for each Share acquired,
Holder shall receive, without cost to Holder, the total number and kind of
securities to which Holder would have been entitled had Holder owned the Shares
of record as of the date the dividend or subdivision occurred.

           2.2   RECLASSIFICATION, EXCHANGE OR SUBSTITUTION.  Upon any
reclassification, exchange, substitution, or other event that results in a
change of the number and/or class of the securities issuable upon exercise or
conversion of this Warrant, Holder shall be entitled to receive, upon exercise
or conversion of this Warrant, the number and kind of securities and property
that Holder would have received for the Shares if this Warrant had been
exercised immediately before such reclassification, exchange, substitution, or
other event. Such an event shall include any automatic conversion of the
outstanding or issuable securities of the Company of the same class or series as
the Shares to common stock pursuant to the terms of the Company's Articles of
Incorporation upon the closing of a registered public offering of the Company's
common stock. The Company or its successor shall promptly issue to Holder a new
Warrant for such new securities or other property. The new Warrant shall provide
for adjustments which shall be as nearly equivalent as may be practicable to the
adjustments provided for in this Article 2 including, without limitation,
adjustments to the Warrant Price and to the number of securities or property
issuable upon exercise of the new Warrant. The provisions of this Section 2.2
shall similarly apply to successive reclassifications, exchanges, substitutions,
or other events.

           2.3   ADJUSTMENTS FOR COMBINATIONS, ETC.  If the outstanding shares
are combined or consolidated, by reclassification or otherwise, into a lesser
number of shares, the Warrant Price shall be proportionately increased.


                                         2
<PAGE>

           2.4   ADJUSTMENTS FOR DILUTING ISSUANCES.  The Warrant Price and the
number of Shares issuable upon exercise of this Warrant or, if the Shares are
Preferred Stock, the number of shares of common stock issuable upon conversion
of the Shares, shall be subject to adjustment, from time to time in the manner
set forth on Exhibit A in the event of Diluting issuances (as defined on Exhibit
A).

           2.5   NO IMPAIRMENT.  The Company shall not, by amendment of its
Articles of Incorporation or through a reorganization, transfer of assets,
consolidation, merger, dissolution, issue, or sale of securities or any other
voluntary action, avoid or seek to avoid the observance or performance of any of
the terms to be observed or performed under this Warrant by the Company, but
shall at all times in good faith assist in carrying out of all the provisions of
this Article 2 and in taking all such action as may be necessary or appropriate
to protect Holder's rights under this Article against impairment. If the Company
takes any action affecting the Shares or its common stock other than as
described above that adversely affects Holder's rights under this Warrant, the
Warrant Price shall be adjusted downward and the number of Shares issuable upon
exercise of this Warrant shall be adjusted upward in such a manner that the
aggregate Warrant Price of this Warrant is unchanged.

           2.6   FRACTIONAL SHARES.  No fractional shares shall be issuable upon
exercise or conversion of the Warrant and the number of Shares to be issued
shall be rounded down to the nearest whole Share. If a fractional share interest
arises upon any exercise or conversion of the Warrant, the Company shall
eliminate such fractional share interest by paying Holder an amount computed by
multiplying the fractional interest by the fair market value of a full Share.

           2.7   CERTIFICATE AS TO ADJUSTMENTS.  Upon each adjustment of the
Warrant Price, the Company at its expense shall promptly compute such
adjustment, and furnish Holder with a certificate of its Chief Financial Officer
setting forth such adjustment and the facts upon which such adjustment is based.
The Company shall, upon written request, furnish Holder a certificate setting
forth the Warrant Price in effect upon the date thereof and the series of
adjustments leading to such Warrant Price.

ARTICLE 3. REPRESENTATIONS AND COVENANTS OF THE COMPANY.

           3.1   REPRESENTATIONS AND WARRANTIES. The Company hereby represents
and warrants to the Holder as follows:

                 (a)   The Initial Warrant Price referenced on the first page of
this Warrant is not greater than (i) the price per share at which the Shares
were issued in the Series E round of equity financing in an arms-length
transaction in which at least $500,000 of the Shares were sold and (ii) the fair
market value of the Shares as of the date of this Warrant.

                 (b)   All shares which may be issued upon the exercise of the
purchase right represented by this Warrant, and all securities, if any, issuable
upon conversion of the Shares, shall, upon issuance, be duly authorized, validly
issued, fully paid and nonassessable, and free of any liens and encumbrances
except for restrictions on transfer provided for herein or under applicable
federal and state securities laws.

                 (c) The Capitalization table attached hereto is true and
correct.

           3.2    NOTICE OF CERTAIN EVENTS. If the Company proposes at any time
(a) to declare any dividend or distribution upon its common stock, whether in
cash, property, stock, or other securities and whether or not a regular cash
dividend; (b) to offer for subscription pro rata to the holders of any class or
series of its stock any additional shares of stock of any class or series or
other rights; (c) to effect any reclassification or recapitalization of common
stock; (d) to merge or consolidate with or into any other corporation, or sell,
lease, license, or convey all or substantially all of its assets, or to
liquidate, dissolve or wind up; or (e) offer holders of registration rights the
opportunity to participate in an underwritten public offering of the company's
securities for cash, then, in connection with each such event, the Company shall
give Holder (1) at least 20 days prior written notice of the date on which a
record will be taken for such dividend, distribution, or subscription rights
(and specifying the date on which the holders of


                                          3
<PAGE>

common stock will be entitled thereto) or for determining rights to vote, if
any, in respect of the matters referred to in (c) and (d) above; (2) in the case
of the matters referred to in (c) and (d) above at least 20 days prior written
notice of the date when the same will take place (and specifying the date on
which the holders of common stock will be entitled to exchange their common
stock for securities or other property deliverable upon the occurrence of such
event); and (3) in the case of the matter referred to in (e) above, the same
notice as is given to the holders of such registration rights.

           3.3   INFORMATION RIGHTS.  So long as the Holder holds this Warrant
and/or any of the Shares, the Company shall deliver to the Holder (a) promptly
after mailing, copies of all notices or other written communications to the
shareholders of the Company, (b) within 90 days after the end of each fiscal
year of the Company, the annual audited financial statements of the Company
certified by independent public accountants of recognized standing and (c) such
other financial statements required under and in accordance with any loan
documents between Holder and the Company (or if there are no such requirements
[or if the subject loan(s) no longer are outstanding]), then within 45 days
after the end of each of the first three quarters of each fiscal year, the
Company's quarterly, unaudited financial statements.

           3.4   REGISTRATION UNDER SECURITIES ACT OF 1933, AS AMENDED.  The
Company agrees that the Shares or, if the Shares are convertible into common
stock of the Company, such common stock, shall be subject to the registration
rights set forth on Exhibit B, if attached.

ARTICLE 4.  MISCELLANEOUS.

           4.1   TERM.  This Warrant is exercisable, in whole or in part, at any
time and from time to time on or before the Expiration Date set forth above.

           4.2   LEGENDS.  This Warrant and the Shares (and the securities
issuable, directly or indirectly, upon conversion of the Shares, if any)
shall be imprinted with a legend in substantially the following form:

   THIS SECURITY HAS NOT BEEN REGISTERED UNDER THE SECURITIES ACT OF 1933, AS
   AMENDED, AND MAY NOT BE SOLD, PLEDGED OR OTHERWISE TRANSFERRED WITHOUT AN
   EFFECTIVE REGISTRATION THEREOF UNDER SUCH ACT OR PURSUANT TO RULE 144 OR
   AN OPINION OF COUNSEL REASONABLY SATISFACTORY TO THE CORPORATION AND ITS
   COUNSEL THAT SUCH REGISTRATION IS NOT REQUIRED.

           4.3   COMPLIANCE WITH SECURITIES LAWS ON TRANSFER.  This Warrant and
the Shares issuable upon exercise of this Warrant (and the securities issuable,
directly or indirectly, upon conversion of the Shares, if any) may not be
transferred or assigned in whole or in part without compliance with applicable
federal and state securities laws by the transferor and the transferee
(including, without limitation, the delivery of investment representation
letters and legal opinions reasonably satisfactory to the Company, as reasonably
requested by the Company).  The Company shall not require Holder to provide an
opinion of counsel if the transfer is to an affiliate of Holder or if there is
no material question as to the availability of current information as referenced
in Rule 144(c).  Holder represents that it has complied with Rule 144(d) and (e)
in reasonable detail, the selling broker represents that it has complied with
Rule 144(f), and the Company is provided with a copy of Holder's notice of
proposed sale.

           4.4   TRANSFER PROCEDURE.  Subject to the provisions of Section 4.3
Holder may transfer all or part of this Warrant or the Shares issuable upon
exercise of this Warrant (or the securities issuable, directly or indirectly,
upon conversion of the Shares, if any) at any time to Silicon Valley Bancshares
or The Silicon Valley Bank Foundation, or to any other transferee by giving the
Company notice of the portion of the Warrant being transferred setting forth the
name, address and taxpayer identification number of the transferee and
surrendering this Warrant to the Company for reissuance to the transferee(s)
(and Holder if applicable).  Unless the Company is filing financial information
with the SEC

                                         4
<PAGE>

pursuant to the Securities Exchange Act of 1934, the Company shall have the
right to refuse to transfer any portion of this Warrant to any person who
directly competes with the Company.

           4.5   NOTICES.  All notices and other communications from the Company
to the Holder, or vice versa, shall be deemed delivered and effective when
given personally or mailed by first-class registered or certified mail, at such
address as may have been furnished to the Company or the Holder, as the case may
be, in writing by the Company or such holder from time to time.  All notices to
be provided under this Warrant shall be sent to the following address:

           Silicon Valley Bank
           Attn: Treasury Department HG100
           3003 Tesman Drive
           Santa Clara, CA 95054

           4.6   WAIVER.  This Warrant and any term hereof may be changed,
waived, discharged or terminated only by an instrument in writing signed by the
party against which enforcement of such change, waiver, discharge or termination
is sought.

           4.7   ATTORNEYS FEES.  In the event of any dispute between the
parties concerning the terms and provisions of this Warrant, the party
prevailing in such dispute shall be entitled to collect from the other party all
costs incurred in such dispute, including reasonable attorneys' fees.

           4.8   GOVERNING LAW.  This Warrant shall be governed by and construed
in accordance with the laws of the State of California, without giving effect to
its principles regarding conflicts of law.

                             "COMPANY"

                             Sonoma Systems

                             By:     /s/ [ILLEGIBLE]
                                    ----------------------------------
                             Name:   [ILLEGIBLE]
                                    --------------------------------
                                    (Print)
                             Title:  Chief Financial Officer, Secretary,
                                     Assistant Treasurer or Assistant
                                     Secretary


                                         5
<PAGE>

                                      APPENDIX 1


                                  NOTICE OF EXERCISE


     1.   The undersigned hereby elects to purchase ______ shares of the
Common/Preferred Series ____ [Strike one] Stock of Sonoma Systems pursuant to
the terms of the attached Warrant, and tenders herewith payment of the purchase
price of such shares in full.

or

     1.   The undersigned hereby elects to convert the attached Warrant into
Shares/cash [strike one] in the manner specified in the Warrant.  This
conversion is exercised with respect to _______________ of the Shares covered by
the Warrant.

     2.   Please issue a certificate or certificates representing said shares in
the name of the undersigned or in such other name as is specified below:

               ------------------------------
                    (Name)


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

               ------------------------------
                    (Address)

     3.   The undersigned represents it is acquiring the shares solely for its
own account and not as a nominee for any other party and not with a view toward
the resale or distribution thereof except in compliance with applicable
securities laws.

                                             ----------------------------------
                                                  (Signature)


--------------------
     (Date)

<PAGE>

                                      EXHIBIT A

                               ANTI-DILUTION PROVISIONS
        (FOR PREFERRED STOCK WARRANTS WITH EXISTING ANTI-DILUTION PROTECTION)


     In the event of the issuance (a "Diluting Issuance") by the Company, after
the Issue Date of the Warrant, of securities at a price per share less than the
Warrant Price, then the number of shares of common stock issuable upon
conversion of the Shares shall be adjusted in accordance with those provisions
(the "Provisions") of the Company's Articles (Certificate) of Incorporation
which apply to Diluting issuances.

     The Company agrees that the Provisions, as in effect on the issue Date,
shall be deemed to remain in full force and effect during the term of the
Warrant notwithstanding any subsequent amendment, waiver or termination thereof
by the Company's shareholders.

     Under no circumstances shall the aggregate Warrant Price payable by the
Holder upon exercise of the Warrant increase as a result of any adjustment
arising from a Diluting issuance.

<PAGE>

                                      EXHIBIT A

                               ANTI-DILUTION PROVISIONS
                 (FOR PREFERRED STOCK OR COMMON STOCK WARRANTS WHERE
               ANTI-DILUTION PROTECTION IS INADEQUATE OR NON-EXISTENT)


     In the event of the issuance (a "Diluting Issuance") by the Company, after
the Issue Date of the Warrant, of securities at a price per share less than the
Warrant Price, or, if the Shares are common stock, less than the then conversion
price of the Company's Series ___ Preferred Stock, then the number of shares of
common stock issuable upon conversion of the Shares, or if the Shares are common
stock, the number of Shares issuable upon exercise of the Warrant, shall be
adjusted as a result of Diluting issuances in accordance with the Holder's
standard form of Anti-Dilution Agreement in effect on the Issue Date.

     Under no circumstances shall the aggregate Warrant Price payable by the
Holder upon exercise of the Warrant increase as a result of any adjustment
arising from a Diluting Issuance.