Voting Agreement - Adaptive Broadband Corp. and WMC Holding LLC


 
     VOTING AGREEMENT, dated as of November 12, 2000 (this "Agreement"), between
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Adaptive Broadband Corporation, a Delaware corporation ("Adaptive") and WMC
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Holding LLC, a Delaware limited liability company ("WMC").
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                                    RECITALS

     Adaptive, Western Multiplex Corporation, a Delaware corporation ("Western")
                                                                       -------
and WA Merger Sub, Inc., a wholly-owned subsidiary of Western ("Merger Sub")
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propose to enter into an Agreement and Plan of Merger, dated as of November 12,
2000 (the "Merger Agreement;" capitalized terms used without definition herein
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having the meanings assigned to them in the Merger Agreement), pursuant to which
Merger Sub would be merged (the "Merger") with and into Adaptive.
                                 ------

     As a condition of its entering into the Merger Agreement, Adaptive has
requested that WMC agree, and WMC has agreed, to enter into this Agreement.

     As of the date hereof, WMC is the record and beneficial owner of 39,796,351
shares of Western Common Stock (the "Existing Shares" and, together with any
                                     ---------------
shares of Western Common Stock or other voting capital stock of Western acquired
after the date hereof, whether upon the exercise of warrants, options,
conversion of convertible securities or otherwise, less any shares of Western
common stock transferred prior to the Effective Time in accordance with the
terms of this Agreement, collectively WMC's "Shares"), representing
                                             ------
approximately 71.6% of the aggregate issued and outstanding shares of Western
Common Stock as of the date hereof.

     Prior to the date hereof, Adaptive and WMC had no agreement, arrangement or
understanding for the purpose of acquiring, holding, voting or disposing of the
Shares.

     In consideration for the agreements contained herein, prior to the date
hereof, the board of directors of Western has approved the agreement of WMC to
vote as provided in this Agreement.

                                   ARTICLE I

                                    VOTING
                                    ------

     1.1. Agreement to Vote.
     -----------------------

     WMC hereby agrees during the term of this Agreement that it shall, and
shall cause the holder of record on any applicable record date to, at the
request of Adaptive, at any meeting (whether annual or special and whether or
not an adjourned or postponed meeting) of stockholders of Western, however
called, or in connection with any written consent of the holders of Western
Common Stock, (a) if a meeting is held, appear at such meeting or otherwise
cause the Shares to be counted as present thereat for purposes of establishing a
quorum, and (b) vote or consent (or cause to be voted or consented), in person
or by proxy, all Shares, and any 

 
other voting securities of Western (whether acquired heretofore or hereafter)
that are beneficially owned (within the meaning of Rule 13d-3 of the Securities
Exchange Act of 1934, as amended), or held of record by WMC or as to which WMC
has, directly or indirectly, the right to vote or direct the voting as of the
relevant record date (collectively, the "Subject Shares"), in favor of the
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approval of the issuance of Western Common Stock in connection with the Merger,
the Merger Agreement and the transactions contemplated thereby. WMC further
agrees to use its reasonable good faith efforts to cause the shareholders of
Western to approve the issuance of Western Common Stock in connection with the
Merger, the Merger Agreement and the transactions and matters contemplated in
connection therewith. In the event Western's board of directors does not call a
meeting of its stockholders to approve the Merger and the transactions and
matters contemplated in connection therewith, WMC agrees to take all action
permitted under the amended and restated certificate of incorporation and bylaws
of Western and under Delaware law necessary to call a meeting of its
stockholders to approve the Merger and the transactions and matters contemplated
in connection therewith.

     1.2. Proxy.
     -----------

     WMC hereby agrees to grant to Adaptive a proxy to vote the Subject Shares
as indicated in Section 1.1 above if WMC fails for any reason to vote the
Subject Shares in accordance with Section 1.1. WMC agrees that such a proxy
would be irrevocable and would be coupled with an interest and agrees that it
will take such further action or execute such other instruments as may be
necessary or desirable to effectuate the intent of such a proxy and hereby
revokes any proxy previously granted by it with respect to the Subject Shares.

     1.3. No Ownership Interest.
     ---------------------------

     Nothing contained in this Agreement shall be deemed to vest in Adaptive any
direct or indirect ownership or incidence of ownership of or with respect to any
Subject Shares. All rights, ownership and economic benefits of and relating to
the Subject Shares shall remain vested in and belong to WMC, and Adaptive shall
have no authority to manage, direct, superintend, restrict, regulate, govern, or
administer any of the policies or operations of Western or exercise any power or
authority to direct WMC in the voting of any of the Subject Shares, except as
otherwise provided herein, or in the performance of WMC's duties or
responsibilities as a stockholder of Western.

     1.4. No Inconsistent Agreements.
     --------------------------------

     WMC hereby covenants and agrees that, except as contemplated by this
Agreement and the Merger Agreement, WMC (a) has not entered, and shall not enter
at any time while this Agreement remains in effect, into any voting agreement or
voting trust with respect to the Shares and (b) has not granted, and shall not
grant at any time while this Agreement remains in effect, a proxy or power of
attorney with respect to the Shares, in either case, which is inconsistent with
WMC's obligations pursuant to this Agreement.

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                                  ARTICLE II

                     REPRESENTATIONS AND WARRANTIES OF WMC
                     -------------------------------------

     WMC hereby represents and warrants to Adaptive as follows:

     2.1. Authorization; Validity of Agreement; Necessary Action.
     ------------------------------------------------------------

     WMC has full power and authority to execute and deliver this Agreement, to
perform WMC's obligations hereunder and to consummate the transactions
contemplated hereby. The execution, delivery and performance by WMC of this
Agreement and the consummation by it of the transactions contemplated hereby
have been duly and validly authorized by WMC and no other actions or proceedings
on the part of WMC are necessary to authorize the execution and delivery by it
of this Agreement and the consummation by it of the transactions contemplated
hereby. This Agreement has been duly executed and delivered by WMC, and,
assuming this Agreement constitutes a valid and binding obligation of Adaptive,
constitutes a valid and binding obligation of WMC, enforceable against it in
accordance with its terms, except that (i) such enforcement may be subject to
applicable bankruptcy, insolvency or other similar laws, now or hereafter in
effect, affecting creditors' rights generally, and (ii) the remedy of specific
performance and injunctive and other forms of equitable relief may be subject to
equitable defenses and to the discretion of the court before which any
proceeding therefor may be brought.

     2.2. Shares.
     ------------

     The Existing Shares are, and all of WMC's Shares from the date hereof
through and on the Closing Date (as defined in the Merger Agreement) have been
and will be, owned beneficially and of record by WMC (subject to any
dispositions of Shares permitted by Section 4.1(a) hereof). As of the date
hereof, the Existing Shares constitute all of the shares of Western Common
Stock, options, warrants, rights to acquire, or other securities convertible or
exchangeable for Western Common Stock owned of record or beneficially by WMC.
WMC has or will have sole voting power, sole power of disposition, sole power to
issue instructions with respect to the matters set forth in Article I hereof,
and sole power to agree to all of the matters set forth in this Agreement, in
each case with respect to all of the Existing Shares and with respect to all of
the Shares on the Closing Date, with no limitations, qualifications or
restrictions on such rights, subject to applicable federal securities laws and
the terms of this Agreement.

     2.3. No Conflicts.
     ------------------

     No filing with, and no permit, authorization, consent or approval of, any
state or Person is necessary for the execution of this Agreement by WMC and the
consummation by WMC of the transactions contemplated hereby (other than (i)
filings under the DGCL required to effect the Merger, (ii) the filing of a
pre-merger notification and report form by Western under the HSR, (iii) the
filing of the Form S-4 and the Joint Proxy Statement/Prospectus by Western and
Adaptive in connection with the Merger, or (iv) as otherwise contemplated by the
Merger Agreement) and neither the execution and delivery of this Agreement by
WMC nor the 

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consummation by WMC of the transactions contemplated hereby nor compliance by
WMC with any of the provisions hereof shall conflict with or result in any
breach of any organizational documents applicable to WMC, result in a violation
or breach of, or constitute (with or without notice or lapse of time or both) a
default (or give rise to any third-party right of termination, cancellation,
material modification or acceleration) under any of the terms, conditions or
provisions of any note, bond, mortgage, indenture, license, contract,
commitment, arrangement, understanding, agreement or other instrument or
obligation of any kind to which WMC is a party or by which its properties or
assets may be bound or violate any order, writ, injunction, decree, judgment,
order, statute, rule or regulation applicable to WMC or any of its properties or
assets.

     2.4. No Liens.
     --------------

     The Existing Shares are, and the Shares on the Closing Date (subject to any
transfers permitted by Section 4.1(a)) will be, held by WMC, or by a nominee or
custodian for the exclusive benefit of WMC, free and clear of all liens, claims,
security interests, proxies, voting trusts or agreements, understandings or
arrangements or any other encumbrances whatsoever, except for any encumbrances
arising hereunder.

                                  ARTICLE III

                  REPRESENTATIONS AND WARRANTIES OF ADAPTIVE
                  ------------------------------------------

     Adaptive represents and warrants to WMC as follows:

     3.1. Power: Binding Agreement.
     ------------------------------

     Adaptive has full corporate power and authority to execute and deliver this
Agreement and to perform all of its obligations under this Agreement. This
Agreement has been duly and validly executed and delivered by Adaptive and
constitutes a valid and binding agreement of Adaptive, enforceable against
Adaptive in accordance with its terms, except that (i) such enforcement may be
subject to applicable bankruptcy, insolvency or other similar laws, now or
hereafter in effect, affecting creditors' rights generally, and (ii) the remedy
of specific performance and injunctive and other forms of equitable relief may
be subject to equitable defenses and to the discretion of the court before which
any proceeding therefor may be brought.

     3.2. No Conflicts.
     ------------------

     No filing with, and no permit, authorization, consent or approval of, any
Person is necessary for the execution of this Agreement by Adaptive and the
consummation by Adaptive of the transactions contemplated hereby and neither the
execution and delivery of this Agreement by Adaptive nor the consummation by
Adaptive of the transactions contemplated hereby nor compliance by Adaptive with
any of the provisions hereof shall conflict with or result in any breach of any
organizational documents applicable to Adaptive, result in a violation or breach
of, or constitute (with or without notice or lapse of time or both) a default
(or give rise to any third-party right of termination, cancellation, material
modification or acceleration) under any of the terms, conditions or provisions
of any note, bond, mortgage, indenture, license, contract, commitment,
arrangement, understanding, agreement or other instrument or obligation of any

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kind to which Adaptive is a party or by which Adaptive's properties or assets
may be bound or violate any order, writ, injunction, decree, judgment, order,
statute, rule or regulation applicable to Adaptive or any of Adaptive's
properties or assets.

                                  ARTICLE IV

                                OTHER COVENANTS
                                ---------------

     4.1. Further Agreements of WMC.
     -------------------------------

          (a) WMC hereby agrees, while this Agreement is in effect, and except 
as contemplated hereby, not to sell, transfer, pledge, encumber, assign or
otherwise dispose of (collectively, a "Transfer") or enforce or permit the
execution of the provisions of any redemption, share purchase or sale,
recapitalization or other agreement with Western or enter into any contract,
option or other arrangement or understanding with respect to the offer for sale,
sale, transfer, pledge, encumbrance, assignment or other disposition of, any of
its Existing Shares, any Shares acquired after the date hereof, any securities
exercisable for or convertible into Western Common Stock, any other capital
stock of Western or any interest in any of the foregoing with any Person, except
to a Person who agrees in writing, in an instrument reasonably acceptable to
Adaptive, to be bound by this Agreement.

          (b) Immediately after the execution of this Agreement (and from time 
to time upon the acquisition by WMC of securities of Western prior to the
expiration of this Agreement) and until the expiration of this Agreement, WMC
shall ensure that each certificate evidencing any securities of Western
transferred by WMC bears a legend in the following form:

     THE SECURITY OR SECURITIES REPRESENTED BY THIS CERTIFICATE MAY NOT BE SOLD,
EXCHANGED OR OTHERWISE TRANSFERRED OR DISPOSED OF EXCEPT IN COMPLIANCE WITH THE
TERMS AND PROVISIONS OF THE VOTING AGREEMENT DATED AS OF NOVEMBER 12, 2000,
BETWEEN THE ISSUER AND WMC HOLDING LLC, AS IT MAY BE AMENDED, A COPY OF WHICH IS
ON FILE AT THE PRINCIPAL EXECUTIVE OFFICES OF THE ISSUER.

          (c) In the event of a stock dividend or distribution, or any change in
Western Common Stock by reason of any stock dividend or distribution, or any
change in Western Common Stock by reason of any stock dividend, split-up,
recapitalization, combination, exchange of shares or the like, the term "Shares"
shall be deemed to refer to and include the Shares as well as all such stock
dividends and distributions and any securities into which or for which any or
all of the Shares may be changed or exchanged or which are received in such
transaction.

          (d) WMC agrees that neither it nor any of the officers and directors 
of it shall, and it shall direct and use its reasonable best efforts to cause
its employees, agents and representatives (including any attorney or accountant
retained by it) not to, directly or indirectly, (i) initiate, solicit, encourage
or knowingly facilitate any inquiries or the making of any proposal or offer
with respect to, or a transaction to effect an Acquisition Proposal relating to
Western (as 

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defined in the Merger Agreement), (ii) have any discussion with or provide any
confidential information or data to any Person relating to an Acquisition
Proposal relating to Western, or engage in any negotiations concerning an
Acquisition Proposal relating to Western, or knowingly facilitate any effort or
attempt to make or implement an Acquisition Proposal relating to Western, (iii)
approve or recommend, or propose publicly to approve or recommend, any
Acquisition Proposal relating to Western or (iv) approve or recommend, or
propose publicly to approve or recommend, or execute or enter into, any letter
of intent, agreement in principle, merger agreement, acquisition agreement,
option agreement or other similar agreement relating to any Acquisition Proposal
relating to Western. WMC agrees that it will, and will cause its officers,
directors and representatives to, immediately cease and cause to be terminated
any activities, discussions or negotiations existing as of the date of this
Agreement with any parties conducted heretofore with respect to any Acquisition
Proposal relating to Western. For the avoidance of doubt, this paragraph 4.1(d)
shall not limit the fiduciary duties to Western of any officer or director of
WMC that is also a director of Western.

                                   ARTICLE V

                                 MISCELLANEOUS
                                 -------------

     5.1. Termination.
     -----------------

     This Agreement shall terminate and no party shall have any rights or duties
hereunder upon the earlier of (a) the Effective Time, (b) a determination by the
Board of Directors of Adaptive that an Acquisition Proposal constitutes a
Superior Proposal under Section 5.4 of the Merger Agreement or (c) termination
of the Merger Agreement pursuant to Section 7.1 thereof. Nothing in this Section
5.1 shall relieve or otherwise limit any party of liability for breach of this
Agreement. Upon any termination of this Agreement, this Agreement shall
thereupon become void and of no further force and effect, and there shall be no
liability in respect of this Agreement or of any transactions contemplated
hereby on the part of any party hereto or any of its directors, officers,
partners, members, stockholders, employees, agents, advisors, representatives or
affiliates; provided, however, that nothing herein shall relieve any party from
any liability for such party's material breach of this Agreement; and provided
further that nothing in this Section 5.1 shall limit, restrict, impair, amend or
otherwise modify the rights, remedies, obligations or liabilities of any person
under any other contract or agreement, including, without limitation, the Merger
Agreement.

     5.2. Further Assurances.
     ------------------------

     From time to time, at the other party's request and without further
consideration, each party hereto shall execute and deliver such additional
documents and take all such further action as may be necessary or appropriate to
consummate the transactions contemplated by this Agreement.

     5.3. Noninterference.
     ---------------------

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     WMC hereby agrees and covenants that it shall not, directly or indirectly,
take any action that would make any representation or warranty contained herein
untrue or incorrect or have the effect of preventing or disabling WMC from
performing its obligations under this Agreement.

     5.4. Notices.
     -------------

     All notices and other communications hereunder shall be in writing and
shall be deemed duly given (a) on the date of delivery if delivered personally,
or by telecopy or facsimile, upon confirmation of receipt, (b) on the first
Business Day following the date of dispatch if delivered by a recognized
next-day courier service, or (c) on the tenth Business Day following the date of
mailing if delivered by registered or certified mail, return receipt requested,
postage prepaid. All notices hereunder shall be delivered as set forth below, or
pursuant to such other instructions as may be designated in writing by the party
to receive such notice:

         (a) if to WMC to:

             WMC Holding LLC
             1196 Borregas Avenue
             Sunnyvale, California 94089
             Fax:  (408) 734-4573
             Attention:  Chief Financial Officer

             with a copy to:

             Simpson Thacher & Bartlett
             10 Universal City Plaza, Suite 1850
             Universal City, California  91608
             Fax:  (818) 755-7009
             Attention:  Daniel Clivner, Esq.

         (b) if to Adaptive to:

             Adaptive Broadband Corporation
             1143 Borregas Avenue
             Sunnyvale, California 94089
             Fax:  (408) 743-3449
             Attention:  General Counsel

             with a copy to:

             Cooley Godward LLP
             One Maritime Plaza, 20th Floor
             San Francisco, California 94111
             Fax: (415) 951-3699
             Attention:  Kenn Guernsey, Esq.

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     5.5. Counterparts.
     ------------------

     This Agreement may be executed in one or more counterparts, all of which
shall be considered one and the same agreement and shall become effective when
one or more counterparts have been signed by each of the parties and delivered
to the other party, it being understood that both parties need not sign the same
counterpart.

     5.6. Governing Law.
     -------------------

     This Agreement shall be governed and construed in accordance with the laws
of the State of Delaware, without regard to conflicts of laws principles
thereof.

     5.7. Submission to Jurisdiction; Waivers.
     -----------------------------------------

     Each of WMC and Adaptive irrevocably agrees that any legal action or
proceeding with respect to this Agreement or for recognition and enforcement of
any judgment in respect hereof brought by the other party hereto or its
successors or assigns may be brought and determined in the Chancery or other
Courts of the State of Delaware, and each of WMC and Adaptive hereby irrevocably
submits with regard to any such action or proceeding for itself and in respect
to its property, generally and unconditionally, to the exclusive jurisdiction of
the aforesaid courts. Each of WMC and Adaptive hereby irrevocably waives, and
agrees not to assert, by way of motion, as a defense, counterclaim or otherwise,
in any action or proceeding with respect to this Agreement, (a) any claim that
it is not personally subject to the jurisdiction of the above-named courts for
any reason other than the failure to lawfully serve process, (b) that it or its
property is exempt or immune from jurisdiction of any such court or from any
legal process commenced in such courts (whether through service of notice,
attachment prior to judgment, attachment in aid of execution of judgment,
execution of judgment or otherwise), (c) to the fullest extent permitted by
applicable law, that (i) the suit, action or proceeding in any such court is
brought in an inconvenient forum, (ii) the venue of such suit, action or
proceeding is improper and (iii) this Agreement, or the subject matter hereof,
may not be enforced in or by such courts and (d) any right to a trial by jury.

     5.8. Amendment.
     ---------------

     This Agreement may not be amended except by an instrument in writing signed
on behalf of each of the parties hereto.

     5.9. Enforcement.
     -----------------

     The parties agree that irreparable damage would occur in the event that any
of the provisions of this Agreement were not performed in accordance with their
specific terms. It is accordingly agreed that the parties shall be entitled to
specific performance of the terms hereof, this being in addition to any other
remedy to which they are entitled at law or in equity, including without
limitation injunctive relief.

     5.10. Entire Agreement.
     -----------------------

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     This Agreement constitutes the entire agreement and supersedes all prior
agreements and understandings, both written and oral, among the parties, or any
of them, with respect to the subject matter hereof.

     5.11. Severability.
     -------------------

     If any provision of this Agreement or any part of any such provision is
held under any circumstances to be invalid or unenforceable in any jurisdiction,
then (a) such provisions or part thereof shall, with respect to such
circumstances and in such jurisdiction, be deemed amended to conform to
applicable laws so as to be valid and enforceable to the fullest possible
extent, (b) the invalidity or unenforceability of such provision or part thereof
under such circumstances and in such jurisdiction shall not affect the validity
or enforceability of such provision or part thereof under any other
circumstances or in any other jurisdiction, and (c) the invalidity or
unenforceability of such provision or part thereof shall not affect the validity
or enforceability of the remainder of such provision or the validity or
enforceability of any other provision of this Agreement. Each provision of this
Agreement is separable from every other provision of this Agreement, and each
part of each provision of this Agreement is separable from every other part of
such provision.

     5.12. Assignment; Binding Effect.
     ---------------------------------

     Except as provided herein, neither this Agreement nor any of the interests
or obligations hereunder may be assigned or delegated by WMC and any attempt or
purported assignment or delegation of any of such interests or obligations shall
be void. Subject to the preceding sentence, this Agreement shall be binding upon
WMC and its successors and assigns, and shall inure to the benefit of Adaptive
and its successors and assigns. Without limiting any of the restrictions set
forth in this Agreement, this Agreement shall be binding upon any Person to whom
any Subject Shares are transferred. Nothing in this Agreement is intended to
confer on any Person (other than Adaptive and its successors and assigns) any
rights or remedies of any nature.

     5.13. Waiver.
     -------------

     No failure on the part of Adaptive to exercise any power, right, privilege
or remedy under this Agreement, and no delay on the part of Adaptive in
exercising any power, right, privilege or remedy under this Agreement, shall
operate as a wavier of such power, right, privilege or remedy; and no single or
partial exercise of any such power, right, privilege or remedy shall preclude
any other or further exercise thereof or of any other power, right, privilege or
remedy. Adaptive shall not be deemed to have waived any claim available to
Adaptive arising out of this Agreement, or any power, right, privilege or remedy
of Adaptive under this Agreement, unless the waiver of such claim, power, right,
privilege or remedy is expressly set forth in a written instrument duly executed
and delivered on behalf of Adaptive; and any such waiver shall not be applicable
or have any effect except in the specific instance in which it is given.

                [Remainder of this page intentionally left blank]

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                  IN WITNESS WHEREOF, WMC and Adaptive have caused this
Agreement to be signed by their respective officers or other authorized persons
thereunto duly authorized as of the date first written above.



                                WMC Holding LLC


                                By: /s/ Jeff Hendren                            
                                   -------------------------------------------
                                   Name:  Jeff Hendren
                                   Title: Vice President



                                By: /s/ Frederick D. Lawrence
                                   -------------------------------------------
                                   Name:  Frederick D. Lawrence 
                                   Title: Chairman and Chief Executive Officer

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