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                                                                   Exhibit 10.33

                                   May 9, 2001

Mr. Jonathan Zakin
Chief Executive Officer
Western Multiplex Corporation
1196 Borregas Avenue
Sunnyvale, California  94089

Dear Jon:

               This will confirm our agreement to amend the Amended and Restated
Employment and Co-Investment Agreement (the "Original Agreement"), dated as of
October 31, 1999, among Ripplewood Partners L.P. ("Ripplewood"), WMC Holding
L.L.C. (formerly, WMC Holding Corp.) ("WMC"), Seaview Holdings, L.L.C.
("Seaview"), Western Multiplex Corporation ("Western Multiplex") and you, as set
forth below. Capitalized terms used but not defined in this letter have the
meanings set forth in the Original Agreement.

       1. Section 1.01(d)(i) of the Original Agreement is amended to raise your
       Salary from $50,000 per annum to a rate of $500,000 per annum, commencing
       on July 1, 2001.

       2. In addition, effective January 2, 2001 and for the remainder of the
       term of your employment by Western Multiplex, you shall be entitled to
       receive a target bonus award of 75% of Salary (i.e. $375,000) based upon
       the achievement of performance targets established by the Western
       Multiplex Board of Directors (the "Bonus"). The Bonus, if any, shall be
       paid by Western Multiplex pursuant to the terms of the Western
       Multiplex's established cash incentive bonus plan as approved by the
       Board of Directors."

       3. Section 1.01(d)(ii) of the Original Agreement is amended to read,
       "Other than Salary described in clause (i) and the Bonus described in the
       letter dated May 9, 2001..."

       4. Western Multiplex has granted you options to purchase 900,000 shares
       of Western Multiplex Class A Common Stock (the "WMUX Options") under the
       terms of the Company's 1999 Stock Incentive Plan. The WMUX Options are
       subject to the terms of the 1999 Stock Incentive Plans as well as the
       terms set forth below:

               (a) The WMUX Options shall vest and become exercisable on January
        1, 2004 (or thereafter as set forth below) if you are a Western
        Multiplex employee through that date, per the following schedule:

               (i) 300,000 WMUX Options shall vest and become exercisable on
               January 1, 2004 if on or before that date the Closing Price of
               the Common Stock has equaled or exceeded $12.50 on at least 55 of
               any 65 consecutive Trading Days (the "Measurement Period"); and
               shall otherwise vest and become exercisable thereafter on the
               date that the Closing Price of the Common Stock has equaled or


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               exceeded $12.50 for the Measurement Period if you remain employed
               through such date;

               (ii) an additional 300,000 WMUX Options shall vest and become
               exercisable on January 1, 2004 if on or before that date the
               Closing Price of the Common Stock has equaled or exceeded $17.50
               for the Measurement Period; and shall otherwise vest and become
               exercisable thereafter on the date that the Closing Price of the
               Common Stock has equaled or exceeded $12.50 for the Measurement
               Period if you remain employed through such date; and

               (iii) the final 300,000 WMUX Options shall vest and become
               exercisable on January 1, 2004 if on or before that date the
               Closing Price of the Common Stock has equaled or exceeded $22.50
               for the Measurement Period; and shall otherwise vest and become
               exercisable thereafter on the date that the Closing Price of the
               Common Stock has equaled or exceeded $22.50 for the Measurement
               Period if you remain employed through such date.

       Notwithstanding the vesting schedule set forth above, all of the WMUX
       Options shall become vested and exercisable upon the earlier of (i) a
       Change in Control of Western Multiplex or (ii) on January 2, 2008 if you
       have remained continuously employed by the Western Multiplex through
       January 2, 2008.

               (b) The WMUX Options shall have an exercise price of $7.00.

               (c) For purposes of this Letter, (i) the term "Closing Price"
        shall mean the last reported sales price regular way or, in case no such
        reported sale takes place on such day, the average of the reported
        closing bid and asked prices regular way, in either case on the
        principal national securities exchange or automated quotation system on
        which the Common Stock is listed and admitted to trading; and (ii) the
        term "Trading Day" shall mean a day on which the principal national
        securities exchange or automated quotation system on which the Common
        Stock is listed and admitted to trading is open and the securities
        listed on such exchange or quotation system may be traded on such
        exchange or quotation system.

       5. The other terms of the Original Agreement shall be unaffected by this
       letter.

       6. This letter may be executed in one or more counterparts.

                                      * * *


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               If the foregoing accurately sets forth your understanding, kindly
        sign and return a copy of this letter, whereupon it shall be a binding
        agreement among us, effective as of the date set forth above.

                                                   Sincerely yours,

                                                   WMC HOLDING L.L.C.


                                                   By: /s/  Jeffrey M. Hendren
                                                       -------------------------
                                                       Name:  Jeffrey M. Hendren
                                                       Title: Secretary


                                                   WESTERN MULTIPLEX CORPORATION

                                                   By: /s/  Amir Zoufonoun
                                                       -------------------------
                                                       Name:  Amir Zoufonoun
                                                       Title: President & COO


        Solely for purposes of Section 14.01 Of the Original Agreement:

        RIPPLEWOOD PARTNERS, L.P.


        By: /s/  Jeffrey M. Hendren
            -------------------------
            Name:  Jeffrey M. Hendren
            Title: Managing Director

        Agreed and accepted:


        SEAVIEW HOLDINGS, L.L.C.


        By: /s/  Jonathan N. Zakin
            -------------------------
            Name:  Jonathan N. Zakin
            Title: Manager

            /s/  Jonathan N. Zakin
            -------------------------
            Jonathan N. Zakin