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                                                                     EXHIBIT 4.2

                             VINA TECHNOLOGIES, INC.


             FOURTH AMENDED AND RESTATED INVESTORS' RIGHTS AGREEMENT

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

                                JANUARY 31, 2000


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                                TABLE OF CONTENTS

<TABLE>
<CAPTION>
                                                                            PAGE
<S> <C>                                                                     <C>
1.  Termination of Prior Agreement............................................1

2.  Registration Rights.......................................................1
        2.1  Definitions......................................................1
        2.2  Request for Registration.........................................2
        2.3  Company Registration.............................................4
        2.4  Obligations of the Company.......................................4
        2.5  Furnish Information..............................................6
        2.6  Expenses of Demand Registration..................................6
        2.7  Expenses of Company Registration.................................6
        2.8  Underwriting Requirements........................................7
        2.9  Delay of Registration............................................7
        2.10  Indemnification.................................................7
        2.11  Reports Under Securities Exchange Act of 1934..................10
        2.12  Form S-3 Registration..........................................10
        2.13  Assignment of Registration Rights..............................11
        2.14  Limitations on Subsequent Registration Rights..................11
        2.15  "Market Stand-Off" Agreement...................................12
        2.16  Termination of Registration Rights.............................12

3.  Covenants of the Company.................................................13
        3.1  Delivery of Financial Statements................................13
        3.2  Inspection......................................................14
        3.3  Termination of Information and Inspection Covenants.............14
        3.4  Right of First Offer............................................14

4.  Miscellaneous............................................................16
        4.1  Successors and Assigns..........................................16
        4.2  Governing Law...................................................16
        4.3  Counterparts....................................................16
        4.4  Titles and Subtitles............................................16
        4.5  Notices.........................................................16
        4.6  Expenses........................................................16
        4.7  Amendments and Waivers..........................................16
        4.8  Severability....................................................16
        4.9  Aggregation of Stock............................................17
        4.10  Entire Agreement; Amendment; Waiver............................17
        4.11  Additional Parties.............................................17
</TABLE>

Schedule A Schedule of Investors


                                       i

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                           INVESTORS' RIGHTS AGREEMENT


        THIS INVESTORS' RIGHTS AGREEMENT is made as of the 31st day of January,
2000, by and between Vina Technologies, Inc., a California corporation (the
"Company"), and the investors listed on Schedule A hereto (the "Investors," each
of which is herein referred to as an "Investor").

                                    RECITALS

        WHEREAS, the Company and certain of the Investors are parties to the
Third Amended and Restated Investors' Rights Agreement, dated October 23, 1998
(the "Prior Agreement");

        WHEREAS, the Company and certain of the Investors are parties to the
Series E Preferred Stock Purchase Agreement of even date herewith (the "Series E
Agreement");

        WHEREAS, in order to induce the Company to enter into the Series E
Agreement and to induce certain of the Investors to invest funds in the Company
pursuant to the Series E Agreement, the Investors and the Company hereby agree
that this Agreement shall govern the rights of the Investors to cause the
Company to register shares of Common Stock issuable to the Investors and certain
other matters as set forth herein;

        NOW, THEREFORE, THE PARTIES HEREBY AGREE AS FOLLOWS:

        1. Termination of Prior Agreement. The parties to the Prior Agreement
(all of whom are parties to this Agreement) hereby agree that the Prior
Agreement is hereby terminated and of no further force and effect.

        2. Registration Rights. The Company covenants and agrees as follows:

            2.1 Definitions. For purposes of this Section 2:

                (a) The term "Act" means the Securities Act of 1933, as amended.

                (b) The term "Form S-3" means such form under the Act as in
effect on the date hereof or any registration form under the Act subsequently
adopted by the SEC which permits inclusion or incorporation of substantial
information by reference to other documents filed by the Company with the SEC.

                (c) The term "Holder" means any person owning or having the
right to acquire Registrable Securities or any assignee thereof in accordance
with Section 2.13 hereof.

                (d) The term "1934 Act" shall mean the Securities Exchange Act
of 1934, as amended.

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                (e) The term "register", "registered," and "registration" refer
to a registration effected by preparing and filing a registration statement or
similar document in compliance with the Act, and the declaration or ordering of
effectiveness of such registration statement or document.

                (f) The term "Registrable Securities" means (i) the Common Stock
issuable or issued upon conversion of the Series A Preferred Stock of the
Company sold pursuant to the Series A Preferred Stock Purchase Agreement, dated
August 1, 1996, between the Company and the Investors listed on Schedule A
therein (the "Series A Agreement"), (ii) the Common Stock issuable or issued
upon conversion of the Series B Preferred Stock of the Company sold pursuant to
the Series B Preferred Stock Purchase Agreement, dated December 23, 1996, as
amended, between the Company and the Investors listed on Schedule A therein (the
"Series B Agreement"), (iii) the Common Stock issuable or issued upon the
conversion of the Series C Preferred Stock of the Company sold pursuant to the
Series C Preferred Stock Purchase Agreement, dated March 3, 1998, as amended,
between the Company and the Investors listed on Schedule A therein (the "Series
C Agreement"), (iv) the Common Stock of the Company issuable or issued upon the
conversion of Series D Preferred Stock of the Company sold pursuant to the
Series D Agreement, (v) the Common Stock of the Company issuable or issued upon
the conversion of Series E Preferred Stock of the Company sold pursuant to the
Series E Agreement, and (vi) any Common Stock of the Company issued as (or
issuable upon the conversion or exercise of any warrant, right or other security
which is issued as) a dividend or other distribution with respect to, or in
exchange for or in replacement of the shares referenced in (i), (ii), (iii),
(iv) and (v) above, excluding in all cases, however, any Registrable Securities
sold by a person in a transaction in which his rights under this Section 2 are
not assigned.

                (g) The number of shares of "Registrable Securities then
outstanding" shall be determined by the number of shares of Common Stock
outstanding which are, and the number of shares of Common Stock issuable
pursuant to then exercisable or convertible securities which are, Registrable
Securities.

                (h) The term "SEC" shall mean the Securities and Exchange
Commission.

            2.2 Request for Registration.

                (a) If the Company shall receive at any time after the earlier
of (i) March 3, 2002, or (ii) six (6) months after the effective date of the
first registration statement for a public offering of securities of the Company
(other than a registration statement relating either to the sale of securities
to employees of the Company pursuant to a stock option, stock purchase or
similar plan or a SEC Rule 145 transaction), a written request from the Holders
of at least thirty percent (30%) of the Registrable Securities then outstanding
that the Company file a registration statement under the Act covering the
registration of Registrable Securities with anticipated aggregate offering
price, net of underwriting discounts and commissions, in excess of $10,000,000,
then the Company shall:

                    (i) within ten (10) days of the receipt thereof, give
written notice of such request to all Holders; and


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                    (ii) effect as soon as practicable, and in any event within
60 days of the receipt of such request, the registration under the Act of all
Registrable Securities which the Holders request to be registered, subject to
the limitations of subsection 2.2(b), within twenty (20) days of the mailing of
such notice by the Company in accordance with Section 4.5.

                (b) If the Holders initiating the registration request hereunder
("Initiating Holders") intend to distribute the Registrable Securities covered
by their request by means of an underwriting, they shall so advise the Company
as a part of their request made pursuant to subsection 2.2(a) and the Company
shall include such information in the written notice referred to in subsection
2.2(a). The underwriter will be selected by the Company and shall be reasonably
acceptable to a majority in interest of the Initiating Holders. In such event,
the right of any Holder to include his Registrable Securities in such
registration shall be conditioned upon such Holder's participation in such
underwriting and the inclusion of such Holder's Registrable Securities in the
underwriting (unless otherwise mutually agreed by a majority in interest of the
Initiating Holders and such Holder) to the extent provided herein. All Holders
proposing to distribute their securities through such underwriting shall
(together with the Company as provided in subsection 2.4(e)) enter into an
underwriting agreement in customary form with the underwriter or underwriters
selected for such underwriting. Notwithstanding any other provision of this
Section 2.2, if the underwriter advises the Initiating Holders in writing that
marketing factors require a limitation of the number of shares to be
underwritten, then the Initiating Holders shall so advise all Holders of
Registrable Securities which would otherwise be underwritten pursuant hereto,
and the number of shares of Registrable Securities that may be included in the
underwriting shall be allocated among all Holders thereof that have requested
such registration, including the Initiating Holders, in proportion (as nearly as
practicable) to the amount of Registrable Securities of the Company owned by
each such Holder; provided, however, that the number of shares of Registrable
Securities to be included in such underwriting shall not be reduced unless all
other securities are first entirely excluded from the underwriting.

                (c) Notwithstanding the foregoing, if the Company shall furnish
to Holders requesting a registration statement pursuant to this Section 2.2, a
certificate signed by the Chief Executive Officer of the Company stating that in
the good faith judgment of the Board of Directors of the Company, it would be
seriously detrimental to the Company and its shareholders for such registration
statement to be filed and it is therefore essential to defer the filing of such
registration statement, the Company shall have the right to defer taking action
with respect to such filing for a period of not more than 120 days after receipt
of the request of the Initiating Holders; provided, however, that the Company
may not utilize this right more than once in any twelve-month period.

                (d) In addition, the Company shall not be obligated to effect,
or to take any action to effect, any registration pursuant to this Section 2.2:

                    (i) After the Company has effected two registrations
pursuant to this Section 2.2 and such registrations have been declared or
ordered effective;

                    (ii) During the period starting with the date sixty (60)
days prior to the Company's good faith estimate of the date of filing of, and
ending on a date one


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hundred eighty (180) days after the effective date of, a registration subject to
Section 2.3 hereof; provided that the Company is actively employing in good
faith all reasonable efforts to cause such registration statement to become
effective; or

                    (iii) If the Initiating Holders propose to dispose of shares
of Registrable Securities that may be immediately registered on Form S-3
pursuant to a request made pursuant to Section 2.12 below.

            2.3 Company Registration. If (but without any obligation to do so)
the Company proposes to register (including for this purpose a registration
effected by the Company for shareholders other than the Holders) any of its
stock or other securities under the Act in connection with the public offering
of such securities solely for cash (other than a registration relating solely to
the sale of securities to participants in a Company stock plan, a registration
on any form which does not include substantially the same information as would
be required to be included in a registration statement covering the sale of the
Registrable Securities or a registration in which the only Common Stock being
registered is Common Stock issuable upon conversion of debt securities which are
also being registered), the Company shall, at such time, promptly give each
Holder written notice of such registration and such notice shall set forth the
basic terms of the proposed registration. Upon the written request of each
Holder given within twenty (20) days after mailing of such notice by the Company
in accordance with Section 4.5, the Company shall, subject to the provisions of
Section 2.8, cause to be registered under the Act all of the Registrable
Securities that each such Holder has requested to be registered.

            2.4 Obligations of the Company. Whenever required under this Section
2 to effect the registration of any Registrable Securities, the Company shall,
as expeditiously as is reasonably possible:

                (a) Prepare and file with the SEC a registration statement with
respect to such Registrable Securities and use its best efforts to cause such
registration statement to become effective, and, upon the request of the Holders
of a majority of the Registrable Securities registered thereunder, keep such
registration statement effective for a period of up to one hundred twenty (120)
days or until the distribution contemplated in the Registration Statement has
been completed; provided, however, that (i) such 120-day period shall be
extended for a period of time equal to the period the Holder refrains from
selling any securities included in such registration at the request of an
underwriter of Common Stock (or other securities) of the Company; and (ii) in
the case of any registration of Registrable Securities on Form S-3 which are
intended to be offered on a continuous or delayed basis, such 120-day period
shall be extended, if necessary, to keep the registration statement effective
until all such Registrable Securities are sold, provided that Rule 415, or any
successor rule under the Act, permits an offering on a continuous or delayed
basis, and provided further that applicable rules under the Act governing the
obligation to file a post-effective amendment permit, in lieu of filing a
post-effective amendment which (I) includes any prospectus required by Section
10(a)(3) of the Act or (II) reflects facts or events representing a material or
fundamental change in the information set forth in the registration statement,
the incorporation by reference of information required to be included in (I) and
(II) above to be contained in periodic reports filed pursuant to Section 13 or
15(d) of the 1934 Act in the registration statement.


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                (b) Prepare and file with the SEC such amendments and
supplements to such registration statement and the prospectus used in connection
with such registration statement as may be necessary to comply with the
provisions of the Act with respect to the disposition of all securities covered
by such registration statement.

                (c) Furnish to the Holders such numbers of copies of a
prospectus, including a preliminary prospectus, in conformity with the
requirements of the Act, and such other documents as they may reasonably request
in order to facilitate the disposition of Registrable Securities owned by them.

                (d) Use its best efforts to register and qualify the securities
covered by such registration statement under such other securities or Blue Sky
laws of such jurisdictions as shall be reasonably requested by the Holders;
provided that the Company shall not be required in connection therewith or as a
condition thereto to qualify to do business or to file a general consent to
service of process in any such states or jurisdictions, unless the Company is
already subject to service in such jurisdiction and except as may be required by
the Act.

                (e) In the event of any underwritten public offering, enter into
and perform its obligations under an underwriting agreement, in usual and
customary form, with the managing underwriter of such offering. Each Holder
participating in such underwriting shall also enter into and perform its
obligations under such an agreement.

                (f) Notify each Holder of Registrable Securities covered by such
registration statement at any time when a prospectus relating thereto is
required to be delivered under the Act of the happening of any event as a result
of which the prospectus included in such registration statement, as then in
effect, includes an untrue statement of a material fact or omits to state a
material fact required to be stated therein or necessary to make the statements
therein not misleading in the light of the circumstances then existing.

                (g) Cause all such Registrable Securities registered pursuant
hereunder to be listed on each securities exchange on which similar securities
issued by the Company are then listed.

                (h) Provide a transfer agent and registrar for all Registrable
Securities registered pursuant hereunder and a CUSIP number for all such
Registrable Securities, in each case not later than the effective date of such
registration.

                (i) Use its best efforts to furnish, at the request of any
Holder requesting registration of Registrable Securities pursuant to this
Section 2, on the date that such Registrable Securities are delivered to the
underwriters for sale in connection with a registration pursuant to this Section
2, if such securities are being sold through underwriters, or, if such
securities are not being sold through underwriters, on the date that the
registration statement with respect to such securities becomes effective, (i) an
opinion, dated such date, of the counsel representing the Company for the
purposes of such registration, in form and substance as is customarily given to
underwriters in an underwritten public offering, addressed to the underwriters,
if any, and to the Holders requesting registration of Registrable Securities and
(ii) a


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letter dated such date, from the independent certified public accountants of the
Company, in form and substance as is customarily given by independent certified
public accountants to underwriters in an underwritten public offering, addressed
to the underwriters, if any, and to the Holders requesting registration of
Registrable Securities.

            2.5 Furnish Information.

                (a) It shall be a condition precedent to the obligations of the
Company to take any action pursuant to this Section 2 with respect to the
Registrable Securities of any selling Holder that such Holder shall furnish to
the Company such information regarding itself, the Registrable Securities held
by it, and the intended method of disposition of such securities as shall be
required to effect the registration of such Holder's Registrable Securities.

                (b) The Company shall have no obligation with respect to any
registration requested pursuant to Section 2.2 or Section 2.12 if, the number of
shares or the anticipated aggregate offering price of the Registrable Securities
to be included in the registration does not equal or exceed the number of shares
or the anticipated aggregate offering price required to originally trigger the
Company's obligation to initiate such registration as specified in subsection
2.2(a) or subsection 2.12(b)(2), whichever is applicable.

            2.6 Expenses of Demand Registration. All expenses other than
underwriting discounts and commissions incurred in connection with
registrations, filings or qualifications pursuant to Section 2.2, including
(without limitation) all registration, filing and qualification fees, printers'
and accounting fees, fees and disbursements of counsel for the Company
(including fees and disbursements of counsel for the Company in its capacity as
counsel to the selling Holders hereunder; if Company counsel does not make
itself available for this purpose, the Company will pay the reasonable fees and
disbursements of one counsel for the selling Holders) shall be borne by the
Company; provided, however, that the Company shall not be required to pay for
any expenses of any registration proceeding begun pursuant to Section 2.2 if the
registration request is subsequently withdrawn at the request of the Holders of
a majority of the Registrable Securities to be registered (in which case all
participating holders shall bear such expenses), unless the Holders of a
majority of the Registrable Securities agree to forfeit their right to one
demand registration pursuant to Section 2.2; provided further, however, that if
at the time of such withdrawal, the Holders have learned of a material adverse
change in the condition, business, or prospects of the Company from that known
to the Holders at the time of their request and have withdrawn the request with
reasonable promptness following disclosure by the Company of such material
adverse change, then the Holders shall not be required to pay any of such
expenses and shall retain their rights pursuant to Section 2.2.

            2.7 Expenses of Company Registration. The Company shall bear and pay
all expenses incurred in connection with any registration, filing or
qualification of Registrable Securities with respect to the registrations
pursuant to Section 2.3 for each Holder (which right may be assigned as provided
in Section 2.13), including (without limitation) all registration, filing, and
qualification fees, printers and accounting fees relating or apportionable
thereto and the fees and disbursements of counsel for the Company in its
capacity as counsel to the selling Holders hereunder; if Company counsel does
not make itself available for this purpose, the Company will pay the reasonable
fees and disbursements of one counsel for the


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selling Holders selected by them, but excluding underwriting discounts and
commissions relating to Registrable Securities.

            2.8 Underwriting Requirements. In connection with any offering
involving an underwriting of shares of the Company's capital stock, the Company
shall not be required under Section 2.3 to include any of the Holders'
securities in such underwriting unless they accept the terms of the underwriting
as agreed upon between the Company and the underwriters selected by it (or by
other persons entitled to select the underwriters), and then only in such
quantity as the underwriters determine in their sole discretion will not
jeopardize the success of the offering by the Company. If the total amount of
securities, including Registrable Securities, requested by shareholders to be
included in such offering exceeds the amount of securities sold other than by
the Company that the underwriters determine in their sole discretion is
compatible with the success of the offering, then the Company shall be required
to include in the offering only that number of such securities, including
Registrable Securities, which the underwriters determine in their sole
discretion will not jeopardize the success of the offering (the securities so
included to be apportioned pro rata among the selling shareholders according to
the total amount of securities entitled to be included therein owned by each
selling shareholder or in such other proportions as shall mutually be agreed to
by such selling shareholders) but in no event shall (i) the amount of securities
of the selling Holders included in the offering be reduced below thirty percent
(30%) of the total amount of securities included in such offering, unless such
offering is the initial public offering of the Company's securities in which
case the selling shareholders may be excluded if the underwriters make the
determination described above and no other shareholder's securities are included
or (ii) notwithstanding (i) above, any shares being sold by a shareholder
exercising a demand registration right similar to that granted in Section 2.2 be
excluded from such offering. For purposes of the preceding parenthetical
concerning apportionment, for any selling shareholder which is a holder of
Registrable Securities and which is a partnership or corporation, the partners,
retired partners and shareholders of such holder, or the estates and family
members of any such partners and retired partners and any trusts for the benefit
of any of the foregoing persons shall be deemed to be a single "selling
shareholder", and any pro-rata reduction with respect to such "selling
shareholder" shall be based upon the aggregate amount of shares carrying
registration rights owned by all entities and individuals included in such
"selling shareholder", as defined in this sentence.

            2.9 Delay of Registration. No Holder shall have any right to obtain
or seek an injunction restraining or otherwise delaying any such registration as
the result of any controversy that might arise with respect to the
interpretation or implementation of this Section 2.

            2.10 Indemnification. In the event any Registrable Securities are
included in a registration statement under this Section 2:

                (a) To the extent permitted by law, the Company will indemnify
and hold harmless each Holder, the executive officers, directors and partners of
each Holder, any underwriter (as defined in the Act) for such Holder and each
person, if any, who controls such Holder or underwriter within the meaning of
the Act or the 1934 Act, against any losses, claims, damages, or liabilities
(joint or several) to which they may become subject under the Act, or the 1934
Act or other federal or state law or otherwise, insofar as such losses, claims,


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damages, or liabilities (or actions in respect thereof) arise out of or are
based upon any of the following statements, omissions or violations
(collectively a "Violation"): (i) any untrue statement or alleged untrue
statement of a material fact contained in such registration statement, including
any preliminary prospectus or final prospectus contained therein or any
amendments or supplements thereto, (ii) the omission or alleged omission to
state therein a material fact required to be stated therein, or necessary to
make the statements therein not misleading, or (iii) any violation or alleged
violation by the Company of the Act, the 1934 Act, any state securities law or
any rule or regulation promulgated under the Act, or the 1934 Act or any state
securities law; and the Company will pay to each such Holder, underwriter or
controlling person, as incurred, any legal or other expenses reasonably incurred
by them in connection with investigating or defending any such loss, claim,
damage, liability, or action; provided, however, that the indemnity agreement
contained in this subsection 2.10(a) shall not apply to amounts paid in
settlement of any such loss, claim, damage, liability, or action if such
settlement is effected without the consent of the Company (which consent shall
not be unreasonably withheld), nor shall the Company be liable in any such case
for any such loss, claim, damage, liability, or action to the extent that it
arises out of or is based upon a Violation which occurs in reliance upon and in
conformity with written information furnished expressly for use in connection
with such registration by any such Holder, underwriter or controlling person.
Except as set forth herein, the indemnified party and any party cooperating in
the defense of such claim shall not settle or compromise any such claim or admit
liability without the express written consent of the indemnifying party. The
indemnified party shall have the right to be represented by an advisory counsel
and accountants, at its own expense, and the indemnified party shall be kept
fully informed of such action, suit or proceeding at all stages thereof whether
or not the indemnified party is so represented. After a period of thirty days
following the date the written notice of such claim was given to the
indemnifying party the indemnified party may settle any such claim (and the
amount of any such settlement shall be subject to indemnification hereunder)
unless within such thirty-day period the indemnifying party shall have provided
the indemnified party with notice and evidence to the indemnified party's
satisfaction that the indemnifying party reasonably disputes such claim and has
the financial ability to meet its indemnification obligations hereunder.
Notwithstanding the foregoing, the indemnified party may immediately cause to be
paid or discharged any asserted claim the non-payment of which would have an
immediate substantial adverse impact on the indemnified party and any claim
which the indemnifying party has not disputed within thirty days of notice as
provided above.

                (b) To the extent permitted by law, each selling Holder will
indemnify and hold harmless the Company, each of its directors, each of its
officers who has signed the registration statement, each person, if any, who
controls the Company within the meaning of the Act, any underwriter, any other
Holder selling securities in such registration statement and any controlling
person of any such underwriter or other Holder, against any losses, claims,
damages, or liabilities (joint or several) to which any of the foregoing persons
may become subject, under the Act, or the 1934 Act or other federal or state law
or otherwise, insofar as such losses, claims, damages, or liabilities (or
actions in respect thereto) arise out of or are based upon any Violation, in
each case to the extent (and only to the extent) that such Violation occurs in
reliance upon and in conformity with written information furnished by such
Holder expressly for use in connection with such registration; and each such
Holder will pay, as incurred, any legal or other expenses reasonably incurred by
any person intended to be indemnified pursuant to this subsection 2.10(b), in
connection with investigating or defending


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any such loss, claim, damage, liability, or action; provided, however, that the
indemnity agreement contained in this subsection 2.10(b) shall not apply to
amounts paid in settlement of any such loss, claim, damage, liability or action
if such settlement is effected without the consent of the Holder, which consent
shall not be unreasonably withheld; provided, that, in no event shall any
indemnity under this subsection 2.10(b) exceed the gross proceeds from the
offering received by such Holder.

                (c) Promptly after receipt by an indemnified party under this
Section 2.10 of notice of the commencement of any action (including any
governmental action), such indemnified party will, if a claim in respect thereof
is to be made against any indemnifying party under this Section 2.10, deliver to
the indemnifying party a written notice of the commencement thereof and the
indemnifying party shall have the right to participate in, and, to the extent
the indemnifying party so desires, jointly with any other indemnifying party
similarly noticed, to assume the defense thereof with counsel mutually
satisfactory to the parties; provided, however, that an indemnified party
(together with all other indemnified parties which may be represented without
conflict by one counsel) shall have the right to retain one separate counsel,
with the fees and expenses to be paid by the indemnifying party, if
representation of such indemnified party by the counsel retained by the
indemnifying party would be inappropriate due to actual or potential differing
interests between such indemnified party and any other party represented by such
counsel in such proceeding. The failure to deliver written notice to the
indemnifying party within a reasonable time of the commencement of any such
action, if prejudicial to its ability to defend such action, shall relieve such
indemnifying party of any liability to the indemnified party under this Section
2.10, but the omission so to deliver written notice to the indemnifying party
will not relieve it of any liability that it may have to any indemnified party
otherwise than under this Section 2.10.

                (d) If the indemnification provided for in this Section 2.10 is
held by a court of competent jurisdiction to be unavailable to an indemnified
party with respect to any loss, liability, claim, damage, or expense referred to
therein, then the indemnifying party, in lieu of indemnifying such indemnified
party hereunder, shall contribute to the amount paid or payable by such
indemnified party as a result of such loss, liability, claim, damage, or expense
in such proportion as is appropriate to reflect the relative fault of the
indemnifying party on the one hand and of the indemnified party on the other in
connection with the statements or omissions that resulted in such loss,
liability, claim, damage, or expense as well as any other relevant equitable
considerations. The relative fault of the indemnifying party and of the
indemnified party shall be determined by reference to, among other things,
whether the untrue or alleged untrue statement of a material fact or the
omission to state a material fact relates to information supplied by the
indemnifying party or by the indemnified party and the parties' relative intent,
knowledge, access to information, and opportunity to correct or prevent such
statement or omission.

                (e) Notwithstanding the foregoing, to the extent that the
provisions on indemnification and contribution contained in the underwriting
agreement entered into in connection with the underwritten public offering are
in conflict with the foregoing provisions, the provisions in the underwriting
agreement shall control.


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                (f) The obligations of the Company and Holders under this
Section 2.10 shall survive the completion of any offering of Registrable
Securities in a registration statement under this Section 2, and otherwise.

                (g) The rights of indemnification contained in this Section 2
shall not be deemed to be the exclusive remedy of the parties hereto and such
rights shall be in addition to any other rights or remedies which any party
hereto may have at law or equity.

            2.11 Reports Under Securities Exchange Act of 1934. With a view to
making available to the Holders the benefits of Rule 144 promulgated under the
Act ("Rule 144") and any other rule or regulation of the SEC that may at any
time permit a Holder to sell securities of the Company to the public without
registration or pursuant to a registration on Form S-3, the Company agrees to:

                (a) make and keep public information available, as those terms
are understood and defined in Rule 144, at all times after ninety (90) days
after the effective date of the first registration statement filed by the
Company for the offering of its securities to the general public;

                (b) take such action, including the voluntary registration of
its Common Stock under Section 12 of the 1934 Act, as is necessary to enable the
Holders to utilize Form S-3 for the sale of their Registrable Securities, such
action to be taken concurrently with the first registration statement filed by
the Company for the offering of its securities to the general public is declared
effective;

                (c) file with the SEC in a timely manner all reports and other
documents required of the Company under the Act and the 1934 Act; and

                (d) furnish to any Holder, so long as the Holder owns any
Registrable Securities, forthwith upon request (i) a written statement by the
Company that it has complied with the reporting requirements of Rule 144 (at any
time after ninety (90) days after the effective date of the first registration
statement filed by the Company), the Act and the 1934 Act (at any time after it
has become subject to such reporting requirements), or that it qualifies as a
registrant whose securities may be resold pursuant to Form S-3 (at any time
after it so qualifies), (ii) a copy of the most recent annual or quarterly
report of the Company and such other reports and documents so filed by the
Company, and (iii) such other information as may be reasonably requested in
availing any Holder of any rule or regulation of the SEC which permits the
selling of any such securities without registration or pursuant to such form.

            2.12 Form S-3 Registration. In case the Company shall receive from
any Holder or Holders of at least twenty percent (20%) of the Registrable
Securities then outstanding a written request or requests that the Company
effect a registration on Form S-3 and any related qualification or compliance
with respect to all or a part of the Registrable Securities owned by such Holder
or Holders, the Company will:

                (a) promptly give written notice of the proposed registration,
and any related qualification or compliance, to all other Holders; and


                                       10
<PAGE>   13

                (b) as soon as practicable, effect such registration and all
such qualifications and compliances as may be so requested and as would permit
or facilitate the sale and distribution of all or such portion of such Holder's
or Holders' Registrable Securities as are specified in such request, together
with all or such portion of the Registrable Securities of any other Holder or
Holders joining in such request as are specified in a written request given
within 15 days after receipt of such written notice from the Company; provided,
however, that the Company shall not be obligated to effect any such
registration, qualification or compliance, pursuant to this Section 2.12: (1) if
Form S-3 is not available for such offering by the Holders; (2) if the Holders,
together with the holders of any other securities of the Company entitled to
inclusion in such registration, propose to sell Registrable Securities and such
other securities (if any) at an aggregate price to the public (net of any
underwriters' discounts or commissions) of less than $1,000,000; (3) if the
Company shall furnish to the Holders a certificate signed by the President of
the Company stating that in the good faith judgment of the Board of Directors of
the Company, it would be seriously detrimental to the Company and its
shareholders for such Form S-3 Registration to be effected at such time, in
which event the Company shall have the right to defer the filing of the Form S-3
registration statement for a period of not more than 60 days after receipt of
the request of the Holder or Holders under this Section 2.12; provided, however,
that the Company shall not utilize this right more than once in any twelve month
period; (4) if the Company has, within the twelve (12) month period preceding
the date of such request, already effected two registrations on Form S-3 for the
Holders pursuant to this Section 2.12; or (5) in any particular jurisdiction in
which the Company would be required to qualify to do business or to execute a
general consent to service of process in effecting such registration,
qualification or compliance.

                (c) Subject to the foregoing, the Company shall file a
registration statement covering the Registrable Securities and other securities
so requested to be registered as soon as practicable after receipt of the
request or requests of the Holders. All expenses incurred in connection with a
registration requested pursuant to Section 2.12, including (without limitation)
all registration, filing, qualification, printer's and accounting fees and the
reasonable fees and disbursements of counsel for the Company, but excluding any
underwriters' discounts or commissions associated with Registrable Securities,
shall be borne by the Company. Registrations effected pursuant to this Section
2.12 shall not be counted as demands for registration or registrations effected
pursuant to Sections 2.2 or 2.3, respectively.

            2.13 Assignment of Registration Rights. The rights to cause the
Company to register Registrable Securities pursuant to this Section 2 may be
assigned (but only with all related obligations) by a Holder to a transferee or
assignee of such securities, provided: (a) the Company is, within a reasonable
time after such transfer, furnished with written notice of the name and address
of such transferee or assignee and the securities with respect to which such
registration rights are being assigned; (b) such transferee or assignee agrees
in writing to be bound by and subject to the terms and conditions of this
Agreement, including without limitation the provisions of Section 2.15 below;
and (c) such assignment shall be effective only if immediately following such
transfer the further disposition of such securities by the transferee or
assignee is restricted under the Act.

            2.14 Limitations on Subsequent Registration Rights. From and after
the date of this Agreement, the Company shall not, without the prior written
consent of the Holders


                                       11
<PAGE>   14

of a majority of the outstanding Registrable Securities, enter into any
agreement with any holder or prospective holder of any securities of the Company
which would allow such holder or prospective holder (a) to include such
securities in any registration filed under Section 2.2 hereof, unless under the
terms of such agreement, such holder or prospective holder may include such
securities in any such registration only to the extent that the inclusion of his
securities will not reduce the amount of the Registrable Securities of the
Holders which is included or (b) to make a demand registration which could
result in such registration statement being declared effective prior to the
earlier of either of the dates set forth in subsection 2.2(a) or within one
hundred twenty (120) days of the effective date of any registration effected
pursuant to Section 2.2.

            2.15 "Market Stand-Off" Agreement. Each Investor hereby agrees that,
during the period of duration specified by the Company and an underwriter of
Common Stock or other securities of the Company, following the date of the first
sale to the public pursuant to a registration statement of the Company filed
under the Act, it shall not, to the extent requested by the Company and such
underwriter, directly or indirectly sell, offer to sell, contract to sell
(including, without limitation, any short sale), grant any option to purchase or
otherwise transfer or dispose of (other than to donees who agree to be similarly
bound) any securities of the Company held by it at any time during such period
except Common Stock included in such registration; provided, however, that:

                (a) such agreement shall be applicable only to the first such
registration statement of the Company which covers Common Stock (or other
securities) to be sold on its behalf to the public in an underwritten offering;
and

                (b) all officers and directors of the Company and all other
persons with registration rights (whether or not pursuant to this Agreement)
enter into similar agreements; and

                (c) such market stand-off time period shall not exceed 180 days.

        In order to enforce the foregoing covenant, the Company may impose
stop-transfer instructions with respect to the Registrable Securities of each
Investor (and the shares or securities of every other person subject to the
foregoing restriction) until the end of such period.

        Notwithstanding the foregoing, the obligations described in this Section
2.15 shall not apply to a registration relating solely to employee benefit plans
on Form S-l or Form S-8 or similar forms which may be promulgated in the future,
or a registration relating solely to a Commission Rule 145 transaction on Form
S-14 or Form S-15 or similar forms which may be promulgated in the future.

            2.16 Termination of Registration Rights.

                (a) No Holder shall be entitled to exercise any right provided
for in this Section 2 after five (5) years following the consummation of the
sale of securities


                                       12
<PAGE>   15

pursuant to a registration statement filed by the Company under the Act in
connection with the initial firm commitment underwritten offering of its
securities to the general public.

                (b) In addition, the right of any Holder to request registration
or inclusion in any registration pursuant to Section 2.3 shall terminate on the
closing of the first Company-initiated registered public offering of Common
Stock of the Company if all shares of Registrable Securities held or entitled to
be held upon conversion by such Holder may immediately be sold under Rule 144
during any 90-day period, or on such date after the closing of the first
Company-initiated registered public offering of Common Stock of the Company as
all shares of Registrable Securities held or entitled to be held upon conversion
by such Holder may immediately be sold under Rule 144 during any 90-day period;
provided, however, that the provisions of this Section 2.16(b) shall not apply
to any Holder who owns more than two percent (2%) of the Company's outstanding
stock until such time as such Holder owns less than two percent (2%) of the
outstanding stock of the Company.

        3. Covenants of the Company.

            3.1 Delivery of Financial Statements. The Company shall deliver to
each Investor:

                (a) as soon as practicable, but in any event within ninety (90)
days after the end of each fiscal year of the Company, an income statement for
such fiscal year, a balance sheet of the Company and statement of shareholder's
equity as of the end of such year, and a schedule as to the sources and
applications of funds for such year, such year-end financial reports to be in
reasonable detail, prepared in accordance with generally accepted accounting
principles ("gaap"), and audited and certified by independent public accountants
of nationally recognized standing selected by the Company;

                (b) as soon as practicable, but in any event within forty-five
(45) days after the end of each of the first three (3) quarters of each fiscal
year of the Company, an unaudited profit or loss statement, schedule as to the
sources and application of funds for such fiscal quarter and an unaudited
balance sheet as of the end of such fiscal quarter;

                (c) within thirty (30) days of the end of each month, an
unaudited income statement and schedule as to the sources and application of
funds and balance sheet for and as of the end of such month, in reasonable
detail;

                (d) as soon as practicable, but in any event thirty (30) days
prior to the end of each fiscal year, a budget and business plan for the next
fiscal year, prepared on a monthly basis, including balance sheets and sources
and applications of funds statements for such months and, as soon as prepared,
any other budgets or revised budgets prepared by the Company;

                (e) with respect to the financial statements called for in
subsections (b) and (c) of this Section 3.1, an instrument executed by the Chief
Financial Officer or President of the Company and certifying that such
financials were prepared in accordance with gaap consistently applied with prior
practice for earlier periods (with the exception of footnotes that may be
required by gaap) and fairly present the financial condition of the


                                       13
<PAGE>   16

Company and its results of operation for the period specified, subject to
year-end audit adjustment;

                (f) such other information relating to the financial condition,
business, prospects or corporate affairs of the Company as the Investor or any
assignee of the Investor may from time to time request, provided, however, that
the Company shall not be obligated under this subsection (f) or any other
subsection of Section 3.1 to provide information which it deems in good faith to
be a trade secret or similar confidential information.

            3.2 Inspection. The Company shall permit each Investor, at such
Investor's expense, to visit and inspect the Company's properties, to examine
its books of account and records and to discuss the Company's affairs, finances
and accounts with its officers, all at such reasonable times as may be requested
by the Investor; provided, however, that the Company shall not be obligated
pursuant to this Section 3.2 to provide access to any information which it
reasonably considers to be a trade secret or similar confidential information.

            3.3 Termination of Information and Inspection Covenants. The
covenants set forth in subsections 3.1(c), (d) and (f) and Section 3.2 shall
terminate as to Investors and be of no further force or effect when the sale of
securities pursuant to a registration statement filed by the Company under the
Act in connection with the firm commitment underwritten offering of its
securities to the general public is consummated or when the Company first
becomes subject to the periodic reporting requirements of Sections 12(g) or
15(d) of the 1934 Act, whichever event shall first occur.

            3.4 Right of First Offer. Subject to the terms and conditions
specified in this paragraph 3.4, the Company hereby grants to each Major
Investor (as hereinafter defined) a right of first offer with respect to future
sales by the Company of its Shares (as hereinafter defined). For purposes of
this Section 3.4, a Major Investor shall mean (i) any Investor who holds at
least 10% of the original investment such Investor makes in the Company pursuant
to the Series A Agreement, Series B Agreement, Series C Agreement, Series D
Agreement or Series E Agreement and (ii) any person who acquires at least 10% of
the Series A Preferred Stock, Series B Preferred Stock, Series C Preferred
Stock, Series D Preferred Stock or Series E Preferred Stock (or the Common Stock
issued upon conversion thereof) issued pursuant to the Series A Agreement,
Series B Agreement, Series C Agreement, Series D Agreement or Series E
Agreement. For purposes of this Section 3.4, the term Investor includes any
general partners and affiliates of an Investor. An Investor shall be entitled to
apportion the right of first offer hereby granted it among itself and its
partners and affiliates in such proportions as it deems appropriate.

        Each time the Company proposes to offer any shares of, or securities
convertible into or exercisable for any shares of, any class of its capital
stock ("Shares"), the Company shall first make an offering of such Shares to
each Major Investor in accordance with the following provisions:

                (a) The Company shall deliver a notice by certified mail
("Notice") to the Major Investors stating (i) its bona fide intention to offer
such Shares, (ii) the number of such Shares to be offered, and (iii) the price
and terms, if any, upon which it proposes to offer such Shares.


                                       14
<PAGE>   17

                (b) Within 20 calendar days after giving of the Notice, the
Major Investor may elect to purchase or obtain, at the price and on the terms
specified in the Notice, up to that portion of such Shares which equals the
proportion that the number of shares of Common Stock issued and held, or
issuable upon conversion of the Series A Preferred Stock, Series B Preferred
Stock, Series C Preferred Stock, Series D Preferred Stock or Series E Preferred
Stock then held, by such Major Investor bears to the total number of shares of
Common Stock of the Company then outstanding (assuming full conversion and
exercise of all convertible or exercisable securities). The Company shall
promptly, in writing, inform each Major Investor which purchases all the shares
available to it ("Fully-Exercising Investor") of any other Major Investor's
failure to do likewise. During the ten-day period commencing after such
information is given, each Fully-Exercising Investor shall be entitled to obtain
that portion of the Shares for which Major Investors were entitled to subscribe
but which were not subscribed for by the Major Investors which is equal to the
proportion that the number of shares of Common Stock issued and held, or
issuable upon conversion of Series A Preferred Stock, Series B Preferred Stock,
Series C Preferred Stock, Series D Preferred Stock or Series E Preferred Stock
then held, by such Fully-Exercising Investor bears to the total number of shares
of Common Stock issued and held, or issuable upon conversion of the Series A
Preferred Stock, Series B Preferred Stock, Series C Preferred Stock, Series D
Preferred Stock or Series E Preferred Stock then held, by all Fully-Exercising
Investors who wish to purchase some of the unsubscribed shares.

                (c) If all Shares which Investors are entitled to obtain
pursuant to subsection 3.4(b) are not elected to be obtained as provided in
subsection 3.4(b) hereof, the Company may, during the 30-day period following
the expiration of the period provided in subsection 3.4(b) hereof, offer the
remaining unsubscribed portion of such Shares to any person or persons at a
price not less than, and upon terms no more favorable to the offeree than those
specified in the Notice. If the Company does not enter into an agreement for the
sale of the Shares within such period, or if such agreement is not consummated
within 30 days of the execution thereof, the right provided hereunder shall be
deemed to be revived and such Shares shall not be offered unless first reoffered
to the Major Investors in accordance herewith.

                (d) The right of first offer in this paragraph 3.4 shall not be
applicable (i) to the issuance or sale of shares of Common Stock (or options
therefor) to employees for the primary purpose of soliciting or retaining their
employment, (ii) to or after consummation of a bona fide, firmly underwritten
public offering of shares of Common Stock, registered under the Act, at an
offering price of at least $7.00 per share (appropriately adjusted for any stock
split, dividend, combination or other recapitalization) and $7,500,000 in the
aggregate, (iii) the issuance of securities pursuant to the conversion or
exercise of convertible or exercisable securities, (iv) the issuance of
securities in connection with a bona fide business acquisition of or by the
Company, whether by merger, consolidation, sale of assets, sale or exchange of
stock or otherwise or (v) the issuance of stock, warrants or other securities or
rights to persons or entities with which the Company has business relationships,
provided such issuances are for other than primarily equity financing purposes.

                (e) The right of first refusal set forth in this Section 3.4 may
not be assigned or transferred, except that (i) such right is assignable by each
Holder to any wholly owned subsidiary or parent of, or to any corporation or
entity that is, within the meaning


                                       15
<PAGE>   18

of the Act, controlling, controlled by or under common control with, any such
Holder, and (ii) such right is assignable between and among any of the Holders.

        4. Miscellaneous.

            4.1 Successors and Assigns. Except as otherwise provided herein, the
terms and conditions of this Agreement shall inure to the benefit of and be
binding upon the respective successors and assigns of the parties (including
transferees of any shares of Registrable Securities). Nothing in this Agreement,
express or implied, is intended to confer upon any party other than the parties
hereto or their respective successors and assigns any rights, remedies,
obligations, or liabilities under or by reason of this Agreement, except as
expressly provided in this Agreement.

            4.2 Governing Law. This Agreement shall be governed by and construed
under the laws of the State of California as applied to agreements among
California residents entered into and to be performed entirely within
California.

            4.3 Counterparts. This Agreement may be executed in two or more
counterparts, each of which shall be deemed an original, but all of which
together shall constitute one and the same instrument.

            4.4 Titles and Subtitles. The titles and subtitles used in this
Agreement are used for convenience only and are not to be considered in
construing or interpreting this Agreement.

            4.5 Notices. Unless otherwise provided, any notice required or
permitted under this Agreement shall be given in writing and shall be deemed
effectively given upon personal delivery to the party to be notified or upon
deposit with the United States Post Office, by registered or certified mail,
postage prepaid and addressed to the party to be notified at the address as set
forth for such party in the records of the Company, or at such other address as
such party may designate by ten (10) days' advance written notice to the other
parties.

            4.6 Expenses. If any action at law or in equity is necessary to
enforce or interpret the terms of this Agreement, the prevailing party shall be
entitled to reasonable attorneys' fees, costs and necessary disbursements in
addition to any other relief to which such party may be entitled.

            4.7 Amendments and Waivers. Any term of this Agreement may be
amended and the observance of any term of this Agreement may be waived (either
generally or in a particular instance and either retroactively or
prospectively), only with the written consent of the Company and the holders of
a majority of the Registrable Securities then outstanding. Any amendment or
waiver effected in accordance with this paragraph shall be binding upon each
holder of any Registrable Securities then outstanding, each future holder of all
such Registrable Securities, and the Company.

            4.8 Severability. If one or more provisions of this Agreement are
held to be unenforceable under applicable law, such provision shall be excluded
from this Agreement



                                       16
<PAGE>   19

and the balance of the Agreement shall be interpreted as if such provision were
so excluded and shall be enforceable in accordance with its terms.

            4.9 Aggregation of Stock. All shares of Registrable Securities held
or acquired by affiliated entities or persons shall be aggregated together for
the purpose of determining the availability of any rights under this Agreement.

            4.10 Entire Agreement; Amendment; Waiver. This Agreement (including
the Exhibits hereto, if any) constitutes the full and entire understanding and
agreement between the parties with regard to the subjects hereof and thereof.

            4.11 Additional Parties. In the event of a subsequent closing with
an investor as provided for in Section 1.2(c) of the Series E Agreement, such
investor shall become a party to this Agreement as an "Investor" upon receipt
from such investor of a fully executed signature page.


                                       17
<PAGE>   20

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



                                     VINA TECHNOLOGIES, INC.


                                     By:  /s/ Stan Kazmierczak
                                          --------------------------------------
                                          Stan Kazmierczak
                                          Secretary


                                     INVESTORS:


                                     LONDON PACIFIC LIFE & ANNUITY
                                     COMPANY, a North Carolina Joint Stock
                                     Life Insurer


                                     By:  /s/ Susan Y. Gressel
                                          --------------------------------------
                                          Susan Y. Gressel
                                          V.P. & Treasurer


                                     SEQUOIA CAPITAL VII,
                                     a California Limited Partnership

                                     SEQUOIA TECHNOLOGY PARTNERS VII,
                                     a California Limited Partnership

                                     SQP 1997

                                     SEQUOIA 1997

                                     SEQUOIA INTERNATIONAL PARTNERS

                                     By:    SC VII-A Management, LLC
                                     a California Limited Liability Company, its
                                     General Partner


                                     By:
                                         ---------------------------------------
                                            Managing Member


                  SIGNATURE PAGE TO INVESTORS' RIGHTS AGREEMENT

<PAGE>   21

                                     VICTORY VENTURES



                                     By:
                                        ----------------------------------------


                                     MIII PARTNERS



                                     By:
                                        ----------------------------------------


                                     BERT L. ZACCARIA


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


                                     TELESOFT PARTNERS IA, L.P.


                                     By:    TeleSoft IA-GP, Inc.
                                            General Partner


                                     By:    /s/ Arjun Gupta
                                            ------------------------------------
                                            Arjun Gupta
                                            President and Chairman


                                     TELESOFT STRATEGIC SIDE FUND I, L.L.C.


                                     By:    /s/ Arjun Gupta
                                            ------------------------------------
                                            Arjun Gupta


                                     TIMARK L.P.


                                     By:
                                         ---------------------------------------
                                         Frank Marshall


                  SIGNATURE PAGE TO INVESTORS' RIGHTS AGREEMENT


<PAGE>   22


                                     KEVIN J. McQUILLAN


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


                                     QUIGLEY, PHILIP J. AND TERESA LYNNE CARSS
                                     QUIGLEY 1997 FAMILY TRUST

                                     -------------------------------------------
                                     By:
                                        ----------------------------------------

                                     SIERRA VENTURES VI


                                     By:
                                        ----------------------------------------
                                     Name:
                                          --------------------------------------
                                     Title:
                                           -------------------------------------


                                     SV ASSOCIATES VI


                                     By:
                                        ----------------------------------------
                                     Name:
                                          --------------------------------------
                                     Title:
                                           -------------------------------------


                                     EQUITIES HOLDINGS LLC


                                     By:
                                        ----------------------------------------
                                     Name:
                                          --------------------------------------
                                     Title:
                                           -------------------------------------

                  SIGNATURE PAGE TO INVESTORS' RIGHTS AGREEMENT


<PAGE>   23


                                     SUMITOMO CORPORATION

                                     -------------------------------------------
                                     By:
                                        ----------------------------------------


                                     SUMITOMO CORPORATION OF AMERICA


                                     -------------------------------------------
                                     By:
                                        ----------------------------------------


                                     EAST RIVER VENTURES


                                     By:
                                        ----------------------------------------
                                     Name:
                                          --------------------------------------
                                     Title:
                                           -------------------------------------


                  SIGNATURE PAGE TO INVESTORS' RIGHTS AGREEMENT


<PAGE>   24



                                     NORTH AMERICA VENTURE FUND, L.P.,
                                     a Cayman Islands Limited Partnership

                                     By:  CDIB North America Venture Management,
                                          L.D.C., a Cayman Islands Limited
                                          Duration Company
                                          General Partner

                                     By:    /s/ Emily Chen
                                          --------------------------------------
                                     Name:  Emily Chen
                                     Title:   Member

                                     By:    /s/ Charles Lau
                                          --------------------------------------
                                     Name:  Charles Lau
                                     Title:   Member


                                     SEQUOIA CAPITAL VII
                                     A CALIFORNIA LIMITED PARTNERSHIP

                                     SEQUOIA TECHNOLOGY PARTNERS VII
                                     A CALIFORNIA LIMITED PARTNERSHIP

                                     SQP 1997

                                     SEQUOIA INTERNATIONAL PARTNERS

                                     By:  SC VII-A Management, LLC
                                     A California Limited Liability Company,
                                     its General Partner


                                     By: /s/ Doug Lyon
                                         ---------------------------------------
                                         Managing Member


                                     GERALD SHALTZ


                                     /s/ Gerald Shaltz
                                     /s/ Sharon A. Shaltz, Trustee
                                     -------------------------------------------


                                     STANLEY L. AND CAROL J. GOODSTEIN


                  SIGNATURE PAGE TO INVESTORS' RIGHTS AGREEMENT


<PAGE>   25


                                     /s/ Stanley L. Goodstein Trustee
                                     /s/ Carol L. Goodstein Trustee
                                     -------------------------------------------


                                     WILLIAM M. McCORMICK, Jr.

                                     /s/    William M. McCormick, Jr.
                                     -------------------------------------------


                                     ADAM McNICOL

                                     /s/ Adam McNicol
                                     -------------------------------------------


                                     JEFF AND STACEY REITMEIR


                                     /s/ Jeff & Stacey Reitmeir
                                     -------------------------------------------


                                     WM. MICHAEL WEST, SANDRA K. WEST


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


                                     PRAVEEN GUPTA


                                            /s/ Praveen Gupta
                                     -------------------------------------------


                                     CHARLES AND MEHRI LAU


                                            /s/ Charles Lau & /s/ Mehri Lau
                                     -------------------------------------------


                                     YEE CHUEN CHEN YANG


                                            /s/ Yee Chuen Chen Yang
                                     -------------------------------------------
                                     By:  Emily Chen


                  SIGNATURE PAGE TO INVESTORS' RIGHTS AGREEMENT


<PAGE>   26




                                     CARMEN CHANG


                                            /s/ Carmen Chang
                                     -------------------------------------------


                                     HAROLD NEWMAN


                                            /s/ Harold Newman
                                     -------------------------------------------


                  SIGNATURE PAGE TO INVESTORS' RIGHTS AGREEMENT


<PAGE>   27


                                     OTHER SHAREHOLDERS:

                                     Frank Walters
                                     -------------------------------------------


                                     /s/ Frank Walters
                                     -------------------------------------------


                                     Michael D. Maher
                                     -------------------------------------------


                                     /s/ Michael D. Maher
                                     -------------------------------------------


                                     Max Straube
                                     -------------------------------------------


                                     /s/ Max Straube
                                     -------------------------------------------


                                     W.R. Hambrecht/ Vina LLC
                                     -------------------------------------------


                                     /s/ Brian Frank
                                     -------------------------------------------


                                     Patricia Ng
                                     -------------------------------------------


                                     /s/ Patricia Ng
                                     -------------------------------------------


                                     Greenacre Venture LLC
                                     -------------------------------------------

                                     /s/ John Murray
                                     -------------------------------------------


                                     Charter Growth Capital II, L.P.
                                     -------------------------------------------

                                     /s/ Kevin J. McQuillan
                                     -------------------------------------------


                  SIGNATURE PAGE TO INVESTORS' RIGHTS AGREEMENT


<PAGE>   28



                                   SCHEDULE A