<PAGE>

                                 CONFIDENTIAL


THE SECURITIES REPRESENTED BY THIS INSTRUMENT HAVE BEEN ACQUIRED FOR INVESTMENT
AND HAVE NOT BEEN REGISTERED UNDER THE SECURITIES ACT OF 1933, AS AMENDED. SUCH
SECURITIES MAY NOT BE SOLD, TRANSFERRED OR PLEDGED IN THE ABSENCE OF SUCH
REGISTRATION OR UNLESS THE COMPANY RECEIVES AN OPINION OF COUNSEL (WHICH MAY BE
COUNSEL FOR THE COMPANY) REASONABLY ACCEPTABLE TO IT STATING THAT SUCH SALE OR
TRANSFER IS EXEMPT FROM THE REGISTRATION AND PROSPECTUS DELIVERY REQUIREMENTS OF
SAID ACT.

 THE SECURITIES EVIDENCED HEREBY ARE SUBJECT TO THE RESTRICTIONS SET FORTH IN AN
AMENDED AND RESTATED RIGHTS AGREEMENT BY AND AMONG THE COMPANY AND CERTAIN
SECURITYHOLDERS OF THE COMPANY (A COPY OF WHICH MAY BE OBTAINED FROM THE
COMPANY), AND BY ACCEPTING ANY INTEREST IN SUCH SECURITIES THE PERSON ACCEPTING
SUCH INTEREST SHALL BE DEEMED TO AGREE TO AND SHALL BECOME BOUND BY ALL THE
PROVISIONS OF SAID AGREEMENT.



Warrant No. 4                                       Number of Shares: 6,000,000
                                                    (subject to adjustment)

Date of Issuance: February 24, 2000

                                 SONOMA SYSTEMS

                          COMMON STOCK PURCHASE WARRANT

                         (Void after February 24, 2005)

         Sonoma Systems, a California corporation (the "Company"), for value
received, hereby certifies that Nortel Networks Inc., or its registered assigns
(the "Registered Holder"), is entitled, subject to the terms and conditions set
forth below, to purchase from the Company, at any time or from time to time on
or after the date of issuance and on or before 5:00 p.m. (San Francisco time) on
February 24, 2005, up to 6,000,000 shares of Common Stock, $.01 par value per
share, of the Company, at a purchase price of $4.00 per share. The shares
purchasable upon exercise of this Warrant, and the purchase price per share,
each as adjusted from time to time pursuant to the provisions of this Warrant,
are hereinafter referred to as the "Warrant Shares" and the "Purchase Price,"
respectively.

         1. EXERCISE.

                  (a) This Warrant may be exercised by the Registered Holder, in
whole or in part and at any time or from time to time (in each case subject to
provisions of subsections 1(e) through 1(h) below), by surrendering this
Warrant, with the purchase form appended hereto as EXHIBIT I duly executed by
the Registered Holder or by the Registered Holder's duly authorized attorney, at
the principal office of the Company, accompanied by payment in full, in lawful

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                                 CONFIDENTIAL

money of the United States, of the Purchase Price payable in respect of the
number of Warrant Shares purchased upon such exercise.

                  (b) The Registered Holder may, at its option, elect to pay
some or all of the Purchase Price payable upon an exercise of this Warrant by
canceling a portion of this Warrant exercisable for such number of Warrant
Shares as is determined by dividing (i) the total Purchase Price so payable in
respect of the number of Warrant Shares being purchased upon such exercise by
(ii) the excess of the Fair Market Value per share of Common Stock (as defined
below) as of the Exercise Date (as defined in subsection 1(c) below) over the
Purchase Price per share. If the Registered Holder wishes to exercise this
Warrant pursuant to this method of payment with respect to the maximum number of
Warrant Shares for which this Warrant is then exercisable that are purchasable
pursuant to this method, then the number of such Warrant Shares so purchasable
shall be equal to the total number of Warrant Shares for which this Warrant is
exercisable as of the Exercise Date, minus the product obtained by multiplying
(x) the total number of Warrant Shares for which this Warrant is exercisable as
of such date by (y) a fraction, the numerator of which shall be the Purchase
Price per share and the denominator of which shall be the Fair Market Value per
share of Common Stock as of the Exercise Date. The Fair Market Value per share
of Common Stock shall be determined as follows:

                           (i) If the Common Stock is listed on a national
securities exchange, the Nasdaq National Market or another nationally recognized
trading system as of the Exercise Date, the Fair Market Value per share of
Common Stock shall be deemed to be the average of the high and low reported sale
prices per share of Common Stock thereon on the trading day immediately
preceding the Exercise Date (provided that if no such price is reported on such
day, the Fair Market Value per share of Common Stock shall be determined
pursuant to clause (ii) of this subsection 1(b)).

                           (ii) If the Common Stock is not listed on a national
securities exchange, the Nasdaq National Market or another nationally recognized
trading system as of the Exercise Date, the Fair Market Value per share of
Common Stock shall be deemed to be the amount most recently determined by the
Board of Directors to represent the fair market value per share of the Common
Stock (including without limitation a determination for purposes of granting
Common Stock options or issuing Common Stock under an employee benefit plan of
the Company); and, upon request of the Registered Holder, the Board of Directors
(or a representative thereof) shall promptly notify the Registered Holder of the
Fair Market Value per share of Common Stock. Notwithstanding the foregoing, if
the Board of Directors has not made such a determination within the three-month
period prior to the Exercise Date, then (A) the Board of Directors shall make a
determination of the Fair Market Value per share of the Common Stock within 15
days of a request by the Registered Holder that it do so, and (B) the exercise
of this Warrant pursuant to this subsection 1(b) shall be delayed until such
determination is made.

                  (c) Each exercise of this Warrant shall be deemed to have been
effected immediately prior to the close of business on the day on which this
Warrant shall have been surrendered to the Company as provided in subsection
1(a) above (the "Exercise Date"). At such time, the person or persons in whose
name or names any certificates for Warrant Shares shall be

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                                 CONFIDENTIAL

issuable upon such exercise as provided in subsection 1(d) below shall be
deemed to have become the holder or holders of record of the Warrant Shares
represented by such certificates.

                  (d) As soon as practicable after the exercise of this Warrant
in whole or in part, and in any event within 10 days (or, if a determination by
the Company's independent auditors is necessary in connection with such exercise
pursuant to clause (ii) of subsection 1(g) below, then 20 days) thereafter (or,
if any determination by the Company's independent auditors made pursuant to
subsection 1(g) below is challenged by the Registered Holder in accordance with
the provisions of subsection 1(h) below, then within 10 days after conclusion of
the procedures specified in such subsection 1(h)), the Company, at its expense,
will cause to be issued in the name of, and delivered to, the Registered Holder,
or as such Registered Holder may direct:

                           (i) a certificate or certificates for the number of
full Warrant Shares to which the Registered Holder shall be entitled upon such
exercise plus, in lieu of any fractional share to which the Registered Holder
would otherwise be entitled, cash in an amount determined pursuant to Section 3
hereof; and

                           (ii) in case such exercise is in part only, a new
warrant or warrants (dated the date hereof) of like tenor, calling in the
aggregate on the face or faces thereof for the number of Warrant Shares equal
(without giving effect to any adjustment therein) to the number of such shares
called for on the face of this Warrant minus the sum of (a) the number of such
shares purchased by the Registered Holder upon such exercise plus (b) the number
of Warrant Shares (if any) covered by the portion of this Warrant cancelled in
payment of the Purchase Price payable upon such exercise pursuant to subsection
1(b) above.

                  (e) Notwithstanding the foregoing, this Warrant shall become
exercisable as follows:

                           (i) with respect to 1,500,000 Warrant Shares (the
"First Tranche Warrant Shares"), on the Original Issue Date (as defined in
subsection 2(a) below); and

                           (ii) with respect to the remaining 4,500,000 Warrant
Shares, on the fifth (5th) anniversary of the Original Issue Date, unless the
exercisability of such remaining Warrant Shares is accelerated pursuant to
subsection 1(f) below.

                  (f) Exercisability of the remaining Warrant Shares referenced
in clause (ii) of subsection 1(e) above shall be accelerated as follows:

                           (i) if the Company recognizes (such recognition, the
"Second Tranche Acceleration Event"), with respect to any period commencing on
January 1, 2000 and ending on or prior to December 31, 2000, revenues of
$28,000,000 or more, an additional 2,000,000 Warrant Shares (the "Second Tranche
Warrant Shares") shall become exercisable as of the date of occurrence of the
Second Tranche Acceleration Event (subject to the provisions of subsections 1(g)
through 1(i) below);

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                                 CONFIDENTIAL

                           (ii) if the Company receives (such receipt, the
"Third Tranche Acceleration Event"), during any period commencing on January 1,
2000 and ending on or prior to December 31, 2000, purchase orders for the
Company's products and/or services in the aggregate amount of $35,000,000 or
more, an additional 1,000,000 Warrant Shares (the "Third Tranche Warrant
Shares") shall become exercisable as of the date of occurrence of the Third
Tranche Acceleration Event (subject to the provisions of subsections 1(g)
through 1(i) below);

                           (iii) if the Company recognizes, with respect to any
period commencing on January 1, 2000 and ending on or prior to December 31,
2000, revenues of $35,000,000 or more, one (1) additional Warrant Share shall
become exercisable, as of the date of recognition by the Company of such
revenues, for each $10.00 of such revenues in excess of $35,000,000 so
recognized by the Company (subject to the provisions of subsections 1(g) through
1(i) below), provided that exercisability of not more than 1,500,000 Warrant
Shares (the "Fourth Tranche Warrant Shares") may be accelerated pursuant to this
clause (iii); and

                           (iv) notwithstanding the foregoing provisions of
subsection 1(e) and this subsection 1(f), if a Change in Control Event (as
defined below) occurs with respect to the Company prior to the earlier of (A)
the date of termination of the OEM Purchase and Sale Agreement, dated as of
February 10, 2000, between the Company and Nortel Networks Inc. (the "OEM
Agreement") or (B) the date (the "IPO Date") of the closing of the Company's
first underwritten firm commitment public offering of the Company's Common Stock
for sale to the public pursuant to a registration statement under the Securities
Act of 1933, as amended (the "Securities Act"), then, effective as of the date
of such Change in Control Event, (x) all of the Third Tranche Warrant Shares and
the Fourth Tranche Warrant Shares shall, to the extent they have not become
exercisable hereunder prior to such date, become exercisable in full regardless
of the satisfaction (or lack thereof) of the conditions set forth in clauses
(ii) and (iii), respectively, of this subsection 1(f), and (y) if such Change in
Control Event is a Special Change in Control Event, then, in addition to the
acceleration of exercisability of the Third Tranche Warrant Shares and the
Second Tranche Warrant Shares pursuant to clause (iv)(x) of this subsection
1(f), 500,000 of the Second Tranche Warrant Shares shall, to the extent they
have not become exercisable hereunder prior to such date, become exercisable
regardless of the satisfaction (or lack thereof) of the conditions set forth in
clause (i) of this subsection 1(f), and the number of Second Tranche Warrant
Shares the acceleration of exercisability of which remains subject to the
satisfaction of the conditions set forth in clause (i) of this subsection 1(f)
shall be reduced to 1,500,000.

                  (g) Any determination of whether the Second Tranche
Acceleration Event or the Third Tranche Acceleration Event has occurred, and any
determination of whether (and to what extent) exercisability of the Fourth
Tranche Warrant Shares has been accelerated hereunder shall, subject to the
provisions of subsection 1(h) below, be made by the Company's independent
auditors (and the Company shall cause such auditors to make such determination
at the Company's expense), (i) as promptly as reasonably practicable upon a
request for such determination by the Registered Holder, (ii) not later than 10
days after any Exercise Date in the event that the corresponding exercise of
this Warrant purports to exercise the same with respect to any Second Tranche
Warrant Shares, Third Tranche Warrant Shares or Fourth Tranche

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                                 CONFIDENTIAL

Warrant Shares which have not been determined to have become exercisable in
accordance with this subsection 1(g) or by operation of clause (iv) of
subsection 1(f) above, and (iii) in any event, not later than 10 days after
the audited annual financial statements of the Company for the year ended
December 31, 2000 are made available by the Company's auditors, in final
form, to the Company and/or any of the Company's stockholders. To the extent
relevant to the determination of whether exercisability of any of the Warrant
Shares has been accelerated pursuant to subsection 1(f) above, all
determinations of "revenue" shall be made in accordance with generally
accepted accounting principles consistently applied.

                  (h) In the event that the Registered Holder disagrees with any
determination made by the Company's auditors pursuant to subsection 1(g) above,
the Registered Holder may, by written notice to the Company given not later than
15 days after the date on which such determination of the Company's auditors was
furnished in writing to the Registered Holder, require that such determination
be audited by an independent accounting firm of national reputation mutually
acceptable to the Company and the Registered Holder (or, if the Company and the
Registered Holder are unable to agree on the identity of such accounting firm
within 10 days, then such firm shall be selected jointly, within another 10 days
thereafter, by the individuals then serving as primary client contacts for the
Company and the Registered Holder at the independent accounting firm or firms
then serving as the auditors for the Company and the Registered Holder,
respectively). Each of the Company and the Registered Holder shall cooperate in
full with such audit and shall use their respective commercially reasonable
efforts to cause such audit to be completed as promptly as practicable. The cost
of such audit shall be borne by the Company unless such audit does not result in
a determination that exercisability of any of the Warrant Shares shall be
accelerated under subsection 1(f) above (in which case the cost of such audit
shall be borne by the Registered Holder), and the conclusions of such audit
shall be final and binding on all parties absent manifest error.

                  (i) For the purposes of this Warrant:

                           (i) "Change in Control Event" with respect to the
Company means:

                                    (A) the acquisition by an individual, entity
or group (within the meaning of Section 13(d)(3) or 14(d)(2) of the Securities
Exchange Act of 1934, as amended (the "Exchange Act")) (a "Person") of
beneficial ownership of any capital stock of the Company if, after such
acquisition, such Person beneficially owns (within the meaning of Rule 13d-3
promulgated under the Exchange Act) more than 50% of either (x) the
then-outstanding shares of Common Stock of the Company (the "Outstanding Company
Common Stock") or (y) the combined voting power of the then-outstanding
securities of the Company generally entitled to vote (the "Outstanding Company
Voting Securities"); provided, however, that for purposes of this paragraph (A),
no acquisition by any corporation or other entity pursuant to a Business
Combination (as defined below) which complies with clauses (x) and (y) of
paragraph (B) of this definition shall constitute a Change in Control Event; or

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                                 CONFIDENTIAL

                                    (B) the consummation of a merger,
consolidation, reorganization, recapitalization or statutory share exchange
involving the Company or a sale or other disposition of all or substantially all
of the assets of the Company (a "Business Combination"), unless, immediately
following such Business Combination, each of the following two conditions is
satisfied: (x) all or substantially all of the individuals and entities who were
the beneficial owners of the Outstanding Company Common Stock and Outstanding
Company Voting Securities immediately prior to such Business Combination
beneficially own, directly or indirectly, more than 50% of the then-outstanding
shares of common stock and the combined voting power of the then-outstanding
securities generally entitled to vote, respectively, of the resulting or
acquiring corporation in such Business Combination (which shall include, without
limitation, a corporation which as a result of such transaction owns the Company
or substantially all of the Company's assets either directly or through one or
more subsidiaries) (such resulting or acquiring corporation is referred to
herein as the "Acquiring Corporation") in substantially the same proportions as
their ownership of the Outstanding Company Common Stock and Outstanding Company
Voting Securities, respectively, immediately prior to such Business Combination
(it being understood that for purposes of the determination of whether or not
such voting power of the then-outstanding securities are owned, directly or
indirectly, in substantially the same proportions as the ownership of
Outstanding Company Common Stock and Outstanding Company Voting Securities,
respectively, any securities transferred pursuant to transfers by a security
holder which is a corporation to a wholly-owned subsidiary of such corporation
or by a security holder which is a closely-held partnership pro rata to the
partners of such partnership or the retired partners of such partnership or to
the estates of any such partners or retired partners or by a security holder
which is a closely-held limited liability company pro rata to the members of
such limited liability company or the retired members of such limited liability
company or to the estates of any such members or retired members, shall be
deemed to be owned in the same proportion as such securities were owned by the
transferring security holder in each such case), and (y) no Person (excluding
the Acquiring Corporation or any employee benefit plan (or related trust)
maintained or sponsored by the Company or by the Acquiring Corporation)
beneficially owns, directly or indirectly, more than 50% of the then-outstanding
shares of common stock of the Acquiring Corporation, or of the combined voting
power of the then-outstanding securities of such corporation generally entitled
to vote (except to the extent that such ownership existed prior to the Business
Combination);

                           (ii) "Special Change in Control Event" means any
Change in Control Event as a result of which (or in connection with which)
any Person that is a direct competitor of Nortel Networks Inc. or any of its
subsidiaries or Affiliates (as defined below) (including, without limitation,
[*], [*] (including [*]), [*] (including [*], [*], and [*]), [*], [*], [*],
[*] and [*], and their respective subsidiaries, Affiliates and successor
entities (and the subsidiaries and Affiliates of any such successor
entities)), acquires beneficial ownership (within the meaning of Rule 13d-3
promulgated under the Exchange Act) of more than 50% of any of (A) the
Outstanding Company Common Stock, (B) the Outstanding Company Voting
Securities, or (C) with respect to any Change in Control Event described in
clause (B) of the definition of "Change in Control Event" above, the then-

* CERTAIN CONFIDENTIAL INFORMATION ON THIS PAGE HAS BEEN OMITTED AND FILED
  SEPARATELY WITH THE SECURITIES AND EXCHANGE COMMISSION.


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                                 CONFIDENTIAL

outstanding shares of common stock or the combined voting power of the
then-outstanding securities generally entitled to vote, respectively, of the
Acquiring Corporation; and

                           (iii) "Affiliate" means, with respect to any
specified Person, (A) any Person that directly or indirectly controls, is
controlled by, or is under common control with such specified Person, or (B) any
Person that is a member of the immediate family of the specified Person.

         2. ADJUSTMENTS.

                  (a)   DILUTING ISSUANCES.

                        (i)   DEFINITIONS. For purposes of this Section 2, the
following definitions shall apply:

                              (A) "OPTION" shall mean rights, options or
warrants to subscribe for, purchase or otherwise acquire Common Stock or
Convertible Securities.

                              (B) "ORIGINAL ISSUE DATE" shall mean the
date on which this Warrant (or any predecessor warrant) was first issued.

                              (C) "CONVERTIBLE SECURITIES" shall mean any
evidences of indebtedness, shares or other securities directly or indirectly
convertible into or exchangeable for Common Stock, but excluding Options.

                              (D) "ADDITIONAL SHARES OF COMMON STOCK"
shall mean all shares of Common Stock issued (or, pursuant to subsection
2(a)(iii) below, deemed to be issued) by the Company after the Original Issue
Date, other than:

                              (I)      shares of Common Stock issued upon
                                       conversion of shares of Series B
                                       Preferred Stock, Series C Preferred
                                       Stock, Series D Preferred Stock or
                                       Series E Preferred Stock (as such terms
                                       are defined in the Amended and Restated
                                       Articles of Incorporation of the Company
                                       as in effect as of the Original Issue
                                       Date (the "Restated Articles"))
                                       (including Series B Preferred Stock,
                                       Series C Preferred Stock, Series D
                                       Preferred Stock and Series E Preferred
                                       Stock issued upon exercise of warrants
                                       then outstanding);

                              (II)    shares of Common Stock issued or issuable
                                      by reason of a dividend, stock split,
                                      split-up or other distribution on shares
                                      of Common Stock that are covered by
                                      subsections 2(b) or 2(c) below;

                              (III)   shares of Common Stock issued or issuable
                                      to officers or employees of, or
                                      consultants to, the Company pursuant


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                                 CONFIDENTIAL

                                      to a stock grant, option plan or purchase
                                      plan or other employee stock incentive
                                      program approved by the Board of Directors
                                      of the Company;

                              (IV)    shares of Common Stock issued or issuable
                                      upon conversion of Convertible Securities
                                      outstanding prior to the Original Issue
                                      Date; or

                              (V)     up to 2,335,194 shares of the Company's
                                      Series E Preferred Stock.

                           (ii) NO ADJUSTMENT OF PURCHASE PRICE. No adjustments
to the Purchase Price shall be made unless the consideration per share
(determined pursuant to subsection 2(a)(v)) for an Additional Share of Common
Stock issued or deemed to be issued by the Company is less than the lesser of
(i) the Purchase Price on the Original Issue Date or (ii) the Purchase Price in
effect immediately prior to the issue of such Additional Shares.

                           (iii) ISSUE OF SECURITIES DEEMED ISSUE OF ADDITIONAL
SHARES OF COMMON STOCK. If the Company at any time or from time to time after
the Original Issue Date shall issue any Options (excluding Options covered by
subsection 2(a)(i)(D)(III) above) or Convertible Securities or shall fix a
record date for the determination of holders of any class of securities entitled
to receive any such Options or Convertible Securities, then the maximum number
of shares of Common Stock (as set forth in the instrument relating thereto
without regard to any provision contained therein for a subsequent adjustment of
such number) issuable upon the exercise of such Options or, in the case of
Convertible Securities and Options therefor, the conversion or exchange of such
Convertible Securities, shall be deemed to be Additional Shares of Common Stock
issued as of the time of such issue or, in case such a record date shall have
been fixed, as of the close of business on such record date, provided that
Additional Shares of Common Stock shall not be deemed to have been issued unless
the consideration per share (determined pursuant to subsection 2(a)(v) hereof)
of such Additional Shares of Common Stock would be less than the Purchase Price
in effect on the date of and immediately prior to such issue, or such record
date, as the case may be, and provided further that in any such case in which
Additional Shares of Common Stock are deemed to be issued:

                                    (A) No further adjustment in the Purchase
Price shall be made upon the subsequent issue of Convertible Securities or
shares of Common Stock upon the exercise of such Options or conversion or
exchange of such Convertible Securities;

                                    (B) If such Options or Convertible
Securities by their terms provide, with the passage of time or otherwise, for
any increase or decrease in the consideration payable to the Company, then upon
the exercise, conversion or exchange thereof, the Purchase Price computed upon
the original issue thereof (or upon the occurrence of a record date with respect
thereto), and any subsequent adjustments based thereon, shall, upon any such
increase or decrease becoming effective, be recomputed to reflect such increase
or decrease insofar as it affects such Options or the rights of conversion or
exchange under such Convertible Securities;

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                                 CONFIDENTIAL

                                    (C) Upon the expiration or termination of
any such unexercised Option, the Purchase Price shall be readjusted, and the
Additional Shares of Common Stock deemed issued as the result of the original
issue of such Option shall not be deemed issued for the purposes of any
subsequent adjustment of the Purchase Price;

                                    (D) In the event of any change in the number
of shares of Common Stock issuable upon the exercise, conversion or exchange of
any such Option or Convertible Security, including, but not limited to, a change
resulting from the anti-dilution provisions thereof, the Purchase Price then in
effect shall forthwith be readjusted to such Purchase Price as would have
obtained had the adjustment which was made upon the issuance of such Option or
Convertible Security not exercised, converted or exchanged prior to such change
been made upon the basis of such change; and

                                    (E) No readjustment pursuant to clause (B)
or (D) above shall have the effect of increasing the Purchase Price to an amount
which exceeds the lower of (i) the Purchase Price on the original adjustment
date, or (ii) the Purchase Price that would have resulted from any issuances of
Additional Shares of Common Stock between the original adjustment date and such
readjustment date.

         In the event the Company, after the Original Issue Date, amends the
terms or reduces the exercise prices of any such Options or Convertible
Securities (whether such Options or Convertible Securities were outstanding on
the Original Issue Date or were issued after the Original Issue Date), then such
Options or Convertible Securities, as so amended, shall be deemed to have been
issued after the Original Issue Date and the provisions of this subsection
2(a)(iii) shall apply.

                           (iv) ADJUSTMENT OF PURCHASE PRICE UPON ISSUANCE OF
ADDITIONAL SHARES OF COMMON STOCK. In the event the Company shall, at any time
after the Original Issue Date, issue Additional Shares of Common Stock
(including Additional Shares of Common Stock deemed to be issued pursuant to
subsection 2(a)(iii)), without consideration or for a consideration per share
less than the Purchase Price in effect immediately prior to such issue, then and
in such event, such Purchase Price shall be reduced, concurrently with such
issue, to a price (calculated to the nearest cent) determined by multiplying
such Purchase Price by a fraction, (A) the numerator of which shall be (1) the
number of shares of Common Stock outstanding immediately prior to such issue
plus (2) the number of shares of Common Stock which the aggregate consideration
received or to be received by the Company for the total number of Additional
Shares of Common Stock so issued would purchase at such Purchase Price; and (B)
the denominator of which shall be the number of shares of Common Stock
outstanding immediately prior to such issue plus the number of such Additional
Shares of Common Stock so issued.

                           (v) DETERMINATION OF CONSIDERATION. For purposes of
this subsection 2(a), the consideration received by the Company for the issue of
any Additional Shares of Common Stock shall be computed as follows:

                               (A) CASH AND PROPERTY: Such consideration shall:

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                                 CONFIDENTIAL

                                    (I)     insofar as it consists of cash, be
                                            computed at the aggregate of cash
                                            received by the Company, excluding
                                            amounts paid or payable for accrued
                                            interest;

                                    (II)    insofar as it consists of property
                                            other than cash, be computed at the
                                            fair market value thereof at the
                                            time of such issue, as determined in
                                            good faith by the Board of
                                            Directors; and

                                    (III)   in the event Additional Shares of
                                            Common Stock are issued together
                                            with other shares or securities or
                                            other assets of the Company for
                                            consideration which covers both, be
                                            the proportion of such consideration
                                            so received, computed as provided in
                                            clauses (I) and (II) above, as
                                            determined in good faith by the
                                            Board of Directors.

                                    (B) OPTIONS AND CONVERTIBLE SECURITIES. The
consideration per share received by the Company for Additional Shares of Common
Stock deemed to have been issued pursuant to subsection 2(a)(iii), relating to
Options and Convertible Securities, shall be determined by dividing

                                            (x) the total amount, if any,
received or receivable by the Company as consideration for the issue of such
Options or Convertible Securities, plus the minimum aggregate amount of
additional consideration (as set forth in the instruments relating thereto,
without regard to any provision contained therein for a subsequent adjustment of
such consideration) payable to the Company upon the exercise of such Options or
the conversion or exchange of such Convertible Securities, or in the case of
Options for Convertible Securities, the exercise of such Options for Convertible
Securities and the conversion or exchange of such Convertible Securities, by

                                            (y) the maximum number of shares of
Common Stock (as set forth in the instruments relating thereto, without regard
to any provision contained therein for a subsequent adjustment of such number)
issuable upon the exercise of such Options or the conversion or exchange of such
Convertible Securities.

                           (vi) MULTIPLE CLOSING DATES. In the event the Company
shall issue on more than one date Additional Shares of Common Stock which are
comprised of shares of the same series or class of Preferred Stock (excluding
shares of Series E Preferred Stock), and such issuance dates occur within a
period of no more than 120 days, then, upon the final such issuance, the
Purchase Price shall be readjusted to give effect to all such issuances as if
they occurred on the date of the final such issuance (and without giving effect
to any adjustments as a result of such prior issuances within such period).

                  (b) ADJUSTMENT FOR STOCK SPLITS AND COMBINATIONS. If the
Company shall at any time or from time to time after the Original Issue Date
effect a subdivision of the outstanding Common Stock, the Purchase Price then in
effect immediately before that subdivision shall be proportionately decreased.
If the Company shall at any time or from time to time after the

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                                 CONFIDENTIAL

Original Issue Date combine the outstanding shares of Common Stock, the
Purchase Price then in effect immediately before the combination shall be
proportionately increased. Any adjustment under this paragraph shall become
effective at the close of business on the date the subdivision or combination
becomes effective.

                  (c) ADJUSTMENT FOR CERTAIN DIVIDENDS AND DISTRIBUTIONS. In the
event the Company at any time, or from time to time after the Original Issue
Date shall make or issue, or fix a record date for the determination of holders
of Common Stock entitled to receive, a dividend or other distribution payable in
additional shares of Common Stock, then and in each such event the Purchase
Price then in effect immediately before such event shall be decreased as of the
time of such issuance or, in the event such a record date shall have been fixed,
as of the close of business on such record date, by multiplying the Purchase
Price then in effect by a fraction:

                           (1) the numerator of which shall be the total number
                  of shares of Common Stock issued and outstanding immediately
                  prior to the time of such issuance or the close of business on
                  such record date, and

                           (2) the denominator of which shall be the total
                  number of shares of Common Stock issued and outstanding
                  immediately prior to the time of such issuance or the close of
                  business on such record date plus the number of shares of
                  Common Stock issuable in payment of such dividend or
                  distribution;

provided, however, if such record date shall have been fixed and such dividend
is not fully paid or if such distribution is not fully made on the date fixed
therefor, the Purchase Price shall be recomputed accordingly as of the close of
business on such record date and thereafter the Purchase Price shall be adjusted
pursuant to this paragraph as of the time of actual payment of such dividends or
distributions.

                  (d) ADJUSTMENT IN NUMBER OF WARRANT SHARES. When any
adjustment is required to be made in the Purchase Price pursuant to subsections
2(a), 2(b) or 2(c), the number of Warrant Shares purchasable upon the exercise
of this Warrant shall be changed to the number determined by dividing (i) an
amount equal to the number of shares issuable upon the exercise of this Warrant
immediately prior to such adjustment, multiplied by the Purchase Price in effect
immediately prior to such adjustment, by (ii) the Purchase Price in effect
immediately after such adjustment (and, without limiting generality of the
foregoing, the number of the First Tranche Warrant Shares, the Second Tranche
Warrant Shares, the Third Tranche Warrant Shares and the Fourth Tranche Warrant
Shares, as well as the number of Warrant Shares subject to the accelerated
exercisability provisions of clause (iv) of subsection 1(f) above, shall be
similarly adjusted).

                  (e) ADJUSTMENTS FOR OTHER DIVIDENDS AND DISTRIBUTIONS. In the
event the Company at any time or from time to time after the Original Issue Date
shall make or issue, or fix a record date for the determination of holders of
Common Stock entitled to receive, a dividend or other distribution payable in
securities of the Company (other than shares of Common Stock) or in cash or
other property (other than cash out of earnings or earned surplus, determined in
accordance with generally accepted accounting principles), then and in each such

                                    -11-

<PAGE>

                                 CONFIDENTIAL

event provision shall be made so that the Registered Holder shall receive upon
exercise hereof, in addition to the number of shares of Common Stock issuable
hereunder, the kind and amount of securities of the Company and/or cash and
other property which the Registered Holder would have been entitled to receive
had this Warrant been exercised into Common Stock on the date of such event and
had the Registered Holder thereafter, during the period from the date of such
event to and including the Exercise Date, retained any such securities
receivable, giving application to all adjustments called for during such period
under this Section 2 with respect to the rights of the Registered Holder.

                  (f) ADJUSTMENT FOR MERGERS OR REORGANIZATIONS, ETC. If there
shall occur any reorganization, recapitalization, consolidation or merger
involving the Company in which the Common Stock is converted into or exchanged
for securities, cash or other property (other than a transaction covered by
subsections 2(b), 2(c) or 2(e)), then, following any such reorganization,
recapitalization, consolidation or merger, the Registered Holder shall receive
upon exercise hereof the kind and amount of securities, cash or other property
which the Registered Holder would have been entitled to receive if, immediately
prior to such reorganization, recapitalization, consolidation or merger, the
Registered Holder had held the number of shares of Common Stock subject to this
Warrant. Notwithstanding the foregoing sentence, if (x) there shall occur any
reorganization, recapitalization, consolidation or merger involving the Company
in which the Common Stock is converted into or exchanged for anything other than
solely equity securities, and (y) the common stock of the acquiring or surviving
company is publicly traded, then, as part of any such reorganization,
recapitalization, consolidation or merger, (i) the Registered Holder shall have
the right thereafter to receive upon the exercise hereof such number of shares
of common stock of the acquiring or surviving company as is determined by
multiplying (A) the number of shares of Common Stock then subject to this
Warrant by (B) a fraction, the numerator of which is the Fair Market Value per
share of Common Stock as of the effective date of such transaction, as
determined pursuant to subsection 1(b), and the denominator of which is the fair
market value per share of common stock of the acquiring or surviving company as
of the effective date of such transaction, as determined in good faith by the
Board of Directors of the Company (using the principles set forth in subsection
1(b) to the extent applicable), and (ii) the exercise price per share of common
stock of the acquiring or surviving company shall be the Purchase Price divided
by the fraction referred to in clause (B) above. In any such case, appropriate
adjustment (as determined in good faith by the Board of Directors of the
Company) shall be made in the application of the provisions set forth herein
with respect to the rights and interests thereafter of the Registered Holder, to
the end that the provisions set forth in this Section 2 (including provisions
with respect to changes in and other adjustments of the Purchase Price) shall
thereafter be applicable, as nearly as reasonably may be, in relation to any
securities, cash or other property thereafter deliverable upon the exercise of
this Warrant.

                  (g) CERTIFICATE AS TO ADJUSTMENTS. Upon the occurrence of each
adjustment or readjustment of the Purchase Price pursuant to this Section 2, the
Company at its expense shall promptly compute such adjustment or readjustment in
accordance with the terms hereof and furnish to the Registered Holder a
certificate setting forth such adjustment or readjustment (including the kind
and amount of securities, cash or other property for which this Warrant shall be
exercisable and the Purchase Price) and showing in detail the facts upon which
such adjustment or readjustment is based. The Company shall, upon the written
request at any time of

                                    -12-

<PAGE>

                                 CONFIDENTIAL

the Registered Holder, furnish or cause to be furnished to the Registered
Holder a certificate setting forth (i) the Purchase Price then in effect and
(ii) the number of shares of Common Stock and the amount, if any, of other
securities, cash or property which then would be received upon the exercise
of this Warrant.

         3. FRACTIONAL SHARES. The Company shall not be required upon the
exercise of this Warrant to issue any fractional shares, but shall make an
adjustment therefor in cash on the basis of the Fair Market Value per share of
Common Stock, as determined pursuant to subsection 1(b) above.

         4. REQUIREMENTS FOR TRANSFER.

            Subject to the provisions of any other written agreement to which
the Company and the Registered Holder are parties or by which they are bound,
this Warrant and the Registered Holder's rights hereunder may be sold,
exchanged, pledged or otherwise transferred in whole (but not in part), and
the Warrant Shares may be sold, exchanged, pledged or otherwise transferred
in whole or in part, in each case to any person or entity.

         5. REPRESENTATIONS, WARRANTIES AND COVENANTS OF THE COMPANY. The
Company hereby represents and warrants to, and covenants with, the Registered
Holder that, as of the Original Issue Date:

            (a) ORGANIZATION, GOOD STANDING AND QUALIFICATION. The Company is
a corporation duly organized, validly existing and in good standing under the
laws of the State of California and has all requisite corporate power and
authority to carry on its business. The Company is duly qualified to transact
business and is in good standing in each jurisdiction in which the failure so
to qualify would have a material adverse effect on the Company's business or
properties.

            (b) CAPITALIZATION. As of immediately prior to the initial
issuance of this Warrant on the Original Issue Date (the "Closing"), the
authorized capital of the Company consists of:

                     (i) 32,562,731 shares of Preferred Stock, 2,363,636
shares of which have been designated Series A Preferred Stock, all of which will
be issued and outstanding immediately prior to the Closing, 1,691,123 shares of
which have been designated Series B Preferred Stock, all of which will be issued
and outstanding immediately prior to the Closing, 17,808,877 shares of which
have been designated Series C Preferred Stock, all of which will be issued and
outstanding immediately prior to the Closing, 6,199,095 shares of which have
been designated Series D Preferred Stock, all of which will be issued and
outstanding immediately prior to Closing, and 4,500,000 shares of which have
been designated Series E Preferred Stock, 2,067,248 of which are issued and
outstanding immediately prior to the Closing. The rights, privileges and
preferences of the Preferred Stock are as stated in the Restated Articles. All
of the outstanding shares of Preferred Stock have been duly authorized, fully
paid and nonassessable and issued in compliance with all applicable federal and
state securities laws.


                                     -13-

<PAGE>

                                 CONFIDENTIAL

                           (ii) 55,000,000 shares of Common Stock, 499,491
shares of which will be issued and outstanding immediately prior to the Closing.
All of the outstanding shares of Common Stock have been duly authorized, fully
paid and are nonassessable and issued in compliance with all applicable federal
and state securities laws.

                           (iii) The Company has reserved 7,825,000 shares of
Common Stock for issuance to officers, directors, employees and consultants of
the Company pursuant to its 1996 Stock Option Plan duly adopted by the Board of
Directors and approved by the Company shareholders (the "1996 STOCK PLAN"). Of
such reserved shares of Common Stock, 466,493 shares have been issued upon
exercise of options previously granted, options to purchase 7,259,500 shares
have been granted and are currently outstanding, and 99,007 shares of Common
Stock remain available for issuance to officers, directors, employees and
consultants pursuant to the 1996 Stock Plan.

                           (iv) The Company has reserved 1,500,000 shares of
Common Stock for issuance to officers, directors, employees and consultants
of the Company pursuant to its 1999 Stock Option Plan duly adopted by the
Board of Directors and approved by the Company shareholders (the "1999 STOCK
PLAN"). Of such reserved shares of Common Stock, no shares have been issued
upon exercise of options previously granted, options to purchase 1,473,400
shares have been granted and are currently outstanding, and 26,600 shares of
Common Stock remain available for issuance to officers, directors, employees
and consultants pursuant to the 1999 Stock Plan.

                           (v) Except for outstanding options issued pursuant to
the 1996 Stock Plan and the 1999 Stock Plan, and except for outstanding warrants
to acquire up to 178,962 shares of Common Stock, there are no outstanding
options, warrants, rights (including conversion or preemptive rights and rights
of first refusal or similar rights) or agreements, orally or in writing, for the
purchase or acquisition from the Company, either directly or indirectly, of any
shares of its capital stock. Except as set forth in the Amended and Restated
Rights Agreement, dated as of the Original Issue Date, among the Company and the
investors set forth on EXHIBIT A attached thereto (the "Rights Agreement"), the
Company has not granted any registration rights to any Person with respect to
any of the Company's securities.

                  (c) AUTHORIZATION. All corporate action on the part of the
Company, its officers, directors and shareholders necessary for the
authorization, issuance, execution and delivery of this Warrant, the Rights
Agreement and the OEM Agreement (collectively, the "Agreements"), the
performance of all obligations of the Company hereunder and thereunder and the
authorization, issuance (or reservation for issuance), sale and delivery of the
Warrant Shares issuable upon exercise of this Warrant (together, the
"Securities") have been taken or will be taken prior to each Closing, and the
Agreements, when executed and delivered by the Company, shall constitute valid
and legally binding obligations of the Company, enforceable against the Company
in accordance with their terms except (i) as limited by applicable bankruptcy,
insolvency, reorganization, moratorium, fraudulent conveyance, and other laws of
general application affecting enforcement of creditors' rights generally, as
limited by laws relating to the availability of specific performance, injunctive
relief, or other equitable remedies, or (ii) to the

                                    -14-

<PAGE>

                                 CONFIDENTIAL

extent the indemnification provisions contained in the Rights Agreement may
be limited by applicable federal or state securities laws.

                  (d) VALID ISSUANCE OF SECURITIES. This Warrant is duly and
validly issued and free of restrictions on transfer other than restrictions on
transfer under this Warrant, the Rights Agreement and applicable state and
federal securities laws. Based in part upon the representations of the
Registered Holder in this Warrant and subject to the provisions of subsection
5(e) below, this Warrant is issued in compliance with all applicable federal and
state securities laws. The Warrant Shares issuable upon exercise of this Warrant
have been duly and validly reserved for issuance, and upon issuance in
accordance with the terms hereof, shall be duly and validly issued, fully paid
and nonassessable and free of restrictions on transfer other than restrictions
on transfer under this Warrant, the Rights Agreement and applicable federal and
state securities laws, and will be issued in compliance with all applicable
federal and state securities laws.

                  (e) GOVERNMENTAL CONSENTS. No consent, approval, order or
authorization of, or registration, qualification, designation, declaration or
filing with, any federal, state or local governmental authority on the part of
the Company is required in connection with the consummation of the transactions
contemplated by this Warrant, except for filings pursuant to Section 25102(f) of
the California Corporate Securities Law of 1968, as amended, and the rules
thereunder, other applicable state securities laws and Regulation D of the
Securities Act.

                  (f) NONCONTRAVENTION; LITIGATION. The execution, delivery and
performance of the Agreements and the consummation of the transactions
contemplated hereby and thereby will not (i) result in any violation of or
default under, or otherwise conflict with, the Restated Articles or the Bylaws
of the Company (as in effect at the Closing or as of any issuance of Warrant
Shares hereunder) or any instrument, judgment, order, writ, decree or contract
to which the Company is a party or by which it is bound or, to the Company's
knowledge, of any provision of federal, local or foreign statute, rule or
regulation applicable to the Company, or (ii) constitute, with or without
passage of time or giving of notice, either a violation of or default under any
such provision, instrument, judgment, order, writ, decree or contract or an
event which results in the creation of any lien, charge or encumbrance upon any
assets of the Company. There is no action, suit, proceeding or investigation
pending or, to the Company's knowledge, currently threatened against the Company
or with respect to the Company's officers or directors, that questions the
validity of the Agreements or the right of the Company to enter into them, or to
consummate the transactions contemplated hereby or thereby, nor is the Company
aware that there is any basis for the foregoing.

         6. REPRESENTATIONS AND WARRANTIES OF THE REGISTERED HOLDER. The
Registered Holder hereby represents and warrants to the Company that, as of the
Original Issue Date:

                  (a) PURCHASE ENTIRELY FOR OWN ACCOUNT. This Warrant is being
acquired by the Registered Holder for investment for the Registered Holder's own
account, not as a nominee or agent, and not with a view to the resale or
distribution of any part thereof, and the Registered Holder has no present
intention of selling, granting any participation in, or otherwise distributing
the same. The Registered Holder does not presently have any contract,
undertaking, agreement

                                    -15-
<PAGE>

                                 CONFIDENTIAL

or arrangement with any person to sell, transfer or grant participations to
such person or to any third person, with respect to any of the Securities.
The Registered Holder has not been formed for the specific purpose of
acquiring the Securities.

                  (b) DISCLOSURE OF INFORMATION. The Registered Holder has had
the opportunity to perform due diligence and ask questions of the Company's
management in connection with transactions contemplated hereby.

                  (c) RESTRICTED SECURITIES. The Registered Holder understands
that the Securities have not been, and will not be, registered under the
Securities Act, by reason of a specific exemption from the registration
provisions of the Securities Act which depends upon, among other things, the
bona fide nature of the investment intent and the accuracy of the Registered
Holder's representations as expressed herein. The Registered Holder understands
that the Securities are "restricted securities" under applicable U.S. federal
and state securities laws and that, pursuant to these laws, the Registered
Holder must hold the Securities indefinitely unless they are registered with the
Securities and Exchange Commission (the "SEC") and qualified by state
authorities, or an exemption from such registration and qualification
requirements is available. The Registered Holder acknowledges that the Company
has no obligation to register or qualify the Securities for resale except as may
be set forth in a separate written agreement to which the Company and the
Registered Holder are parties or by which they are bound. The Registered Holder
further acknowledges that if an exemption from registration or qualification is
available, it may be conditioned on various requirements including, but not
limited to, the time and manner of sale, the holding period for the Securities,
and requirements relating to the Company which are outside of the Registered
Holder's control and which the Company is under no obligation and may not be
able to satisfy.

                  (d) NO PUBLIC MARKET. The Registered Holder understands that
no public market now exists for any of the securities issued by the Company, and
that the Company has made no assurances that a public market will ever exist for
the Securities.

                  (e) ACCREDITED INVESTOR. The Registered Holder is an
accredited investor as defined in Rule 501(a) of Regulation D promulgated under
the Securities Act.

         7. NO IMPAIRMENT. The Company will not, by amendment of its charter or
through any 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 of this Warrant,
but will at all times in good faith assist in the carrying out of all such terms
and in the taking of all such action as may be necessary or appropriate in order
to protect the rights of the holder of this Warrant against impairment.

         8. NOTICES OF RECORD DATE, ETC. In the event:

                  (a) the Company shall take a record of the holders of its
Common Stock (or other stock or securities at the time deliverable upon the
exercise of this Warrant) for the purpose of entitling or enabling them to
receive any dividend or other distribution, or to receive any right to subscribe
for or purchase any shares of stock of any class or any other securities, or to
receive any other right; or

                                     -16-

<PAGE>

                                 CONFIDENTIAL

                  (b) of any capital reorganization of the Company, any
reclassification of the Common Stock of the Company, any consolidation or merger
of the Company with or into another corporation (other than a consolidation or
merger in which the Company is the surviving entity and its Common Stock is not
converted into or exchanged for any other securities or property), or any
transfer of all or substantially all of the assets of the Company; or

                  (c) of the voluntary or involuntary dissolution, liquidation
or winding-up of the Company,

then, and in each such case, the Company will mail or cause to be mailed to
the Registered Holder a notice specifying, as the case may be, (i) the record
date for such dividend, distribution or right, and the amount and character
of such dividend, distribution or right, or (ii) the effective date on which
such reorganization, reclassification, consolidation, merger, transfer,
dissolution, liquidation or winding-up is to take place, and the time, if any
is to be fixed, as of which the holders of record of Common Stock (or such
other stock or securities at the time deliverable upon the exercise of this
Warrant) shall be entitled to exchange their shares of Common Stock (or such
other stock or securities) for securities or other property deliverable upon
such reorganization, reclassification, consolidation, merger, transfer,
dissolution, liquidation or winding-up. Such notice shall be mailed at least
thirty (30) days prior to the record date or effective date for the event
specified in such notice.

         9. RESERVATION OF STOCK. The Company will at all times reserve and keep
available, solely for issuance and delivery upon the exercise of this Warrant,
such number of Warrant Shares and other securities, cash and/or property, as
from time to time shall be issuable upon the exercise of this Warrant.

         10. EXCHANGE OF WARRANTS. Upon the surrender by the Registered Holder,
properly endorsed, to the Company at the principal office of the Company, the
Company will, subject to the provisions of Section 4 hereof, issue and deliver
to or upon the order of such Holder, at the Company's expense, a new Warrant or
Warrants of like tenor, in the name of the Registered Holder or as the
Registered Holder (upon payment by the Registered Holder of any applicable
transfer taxes) may direct, calling in the aggregate on the face or faces
thereof for the number of shares of Common Stock (or other securities, cash
and/or property) then issuable upon exercise of this Warrant.

         11. REPLACEMENT OF WARRANTS. Upon receipt of evidence reasonably
satisfactory to the Company of the loss, theft, destruction or mutilation of
this Warrant, the Company will issue, in lieu thereof, a new Warrant of like
tenor.

         12. TRANSFERS, ETC.

                  (a) The Company will maintain a register containing the name
and address of the Registered Holder of this Warrant. The Registered Holder may
change its or his address as shown on the warrant register by written notice to
the Company requesting such change.

                                    -17-

<PAGE>

                                 CONFIDENTIAL

                  (b) Subject to the provisions of Section 4 hereof, this
Warrant and all rights hereunder are transferable, in whole or in part, upon
surrender of this Warrant with a properly executed assignment (in the form of
EXHIBIT II hereto) at the principal office of the Company.

                  (c) Until any transfer of this Warrant is made in the warrant
register, the Company may treat the Registered Holder as the absolute owner
hereof for all purposes.

         13. MAILING OF NOTICES, ETC. All notices and other communications from
the Company to the Registered Holder shall be mailed by first-class certified or
registered mail, postage prepaid, to the address last furnished to the Company
in writing by the Registered Holder. All notices and other communications from
the Registered Holder or in connection herewith to the Company shall be mailed
by first-class certified or registered mail, postage prepaid, to the Company at
its principal office set forth below. If the Company should at any time change
the location of its principal office to a place other than as set forth below,
it shall give prompt written notice to the Registered Holder and thereafter all
references in this Warrant to the location of its principal office at the
particular time shall be as so specified in such notice.

         14. NO RIGHTS AS STOCKHOLDER. Until the exercise of this Warrant, the
Registered Holder shall not have or exercise any rights by virtue hereof as a
stockholder of the Company. Notwithstanding the foregoing, in the event (i) the
Company effects a split of the Common Stock by means of a stock dividend and the
Purchase Price of and the number of Warrant Shares are adjusted as of the date
of the distribution of the dividend (rather than as of the record date for such
dividend), and (ii) the Registered Holder exercises this Warrant between the
record date and the distribution date for such stock dividend, the Registered
Holder shall be entitled to receive, on the distribution date, the stock
dividend with respect to the shares of Common Stock acquired upon such exercise,
notwithstanding the fact that such shares were not outstanding as of the close
of business on the record date for such stock dividend.

         15. CHANGE OR WAIVER. Any term of this Warrant may be changed or waived
only by an instrument in writing signed by the party against which enforcement
of the change or waiver is sought.

         16. SECTION HEADINGS. The section headings in this Warrant are for the
convenience of the parties and in no way alter, modify, amend, limit or restrict
the contractual obligations of the parties.

         17. GOVERNING LAW. This Warrant will be governed by and construed in
accordance with the internal laws of the State of California (without reference
to the conflicts of law provisions thereof).

                                    -18-

<PAGE>

                                 CONFIDENTIAL


         EXECUTED as of the Date of Issuance indicated above.

                                         SONOMA SYSTEMS


                                         By:     /s/  Steven M. Waszak
                                             ---------------------------------
[CORPORATE SEAL]                         Title:   Chief Financial Officer
                                                ------------------------------
                                         Address (Principal Office):

                                                 4640 Admiralty Way, Suite 600

                                                 Marina del Rey, CA 90292

ATTEST:

_________________________


                                       -19-

<PAGE>

                                 CONFIDENTIAL


                                                                       EXHIBIT I

                                  PURCHASE FORM

To:_________________                                         Dated:____________

         The undersigned, pursuant to the provisions set forth in the attached
Warrant (No. ___), hereby irrevocably elects to purchase (CHECK APPLICABLE BOX):

         / /   _____ shares of the Common Stock covered by such Warrant; or

         / /   the maximum number of shares of Common Stock for which such
               Warrant is presently exercisable pursuant to the cashless
               exercise procedure set forth in Section 1(b).

         The undersigned herewith makes payment of the full purchase price for
such shares at the price per share provided for in such Warrant, which is
$________. Such payment takes the form of (CHECK APPLICABLE BOX OR BOXES):

         / /   $______ in lawful money of the United States; and/or

         / /   the cancellation of such portion of the attached Warrant as
               is exercisable for a total of _____ Warrant Shares (using a
               Fair Market Value of $_____ per share for purposes of this
               calculation); and/or

         / /   the cancellation of such number of Warrant Shares as is
               necessary, in accordance with the formula set forth in Section
               1(b), to exercise such Warrant with respect to the maximum
               number of Warrant Shares for which such Warrant is presently
               exercisable that are purchasable pursuant to the cashless
               exercise procedure set forth in Section 1(b).

                                 Signature: ________________________

                                 Address: __________________________

                                          __________________________


                                     -20-

<PAGE>

                                 CONFIDENTIAL


                                                                      EXHIBIT II

                                 ASSIGNMENT FORM

         FOR VALUE RECEIVED, ________________________________________ hereby
sells, assigns and transfers all of the rights of the undersigned under the
attached Warrant (No. ____) with respect to the number of shares of Common Stock
covered thereby set forth below, unto:

Name of Assignee            Address                     No. of Shares
----------------            -------                     -------------




Dated:________________                Signature:________________________________



                                    -21-