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                                                                   EXHIBIT 10.64
[LOGO OF GREYROCK CAPITAL APPEARS HERE]


                            Antidilution Agreement

Issuer:        P-COM, INC.

Address:       3175 S. Winchester Blvd.
               Campbell, California 95008

Date:          January 14, 2000


THIS AGREEMENT is entered into as of the above date by and between GREYROCK
CAPITAL, a Division of Banc of America Commercial Finance Corporation
("Purchaser"), whose address is 10880 Wilshire Blvd. Suite 1850, Los Angeles, CA
90024, and the above Company, whose address is set forth above.

                                   RECITALS

  A.   Concurrently with the execution of this Antidilution Agreement, the
Purchaser is purchasing from the Company a Warrant to Purchase Stock (the
"Warrant") pursuant to which Purchaser has the right to acquire from the Company
the Shares (as defined in the Warrant).

  B.   By this Antidilution Agreement, the Purchaser and the Company desire to
set forth the adjustment in the number of Shares issuable upon exercise of the
Warrant as a result of a diluting issuance.

  C.   Capitalized terms used herein shall have the same meaning as set forth in
the Warrant.

  NOW, THEREFORE, in consideration of the mutual promises, covenants and
conditions hereinafter set forth, the parties hereto mutually agree as follows:

  1.   Definitions. As used in this Antidilution Agreement, the following terms
have the following respective meanings:

  (a)  "Option" means any right, option, or warrant to subscribe for, purchase,
or otherwise acquire common stock or Convertible Securities.

  (b)  "Convertible Securities" means any evidences of indebtedness, shares of
stock, or other securities directly or indirectly convertible into or
exchangeable for common stock.

  (c)  "Issue" means to grant, issue, sell, assume, or fix a record date for
determining persons entitled to receive, any security (including Options),
whichever of the foregoing is the first to occur.

  (d)  "Additional Common Shares" means all common stock (including reissued
shares) issued (or deemed to be issued pursuant to Section 2) after the date of
the Warrant. Additional Common Shares does not include, however, (i) any common
stock issued in a transaction described in Sections 2.1 and 2.2 of the Warrant;
any common stock Issued upon exercise or conversion of any Option or Convertible
Securities outstanding on the date of the Warrant; (ii) the Shares; or (iii)
common stock issued as incentive or in a nonfinancing transaction to employees,
officers, directors, or consultants to the Company or under any Option or
Convertible Security so issued (including all transactions under the employee's
stock purchase plan); or (iv) any common stock issued in connection with (or
under Options or Convertible Securities issued in connection with) vendor or
customer relationships or strategic partnering, provided that the foregoing
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shall not include issuances in connection with merger or acquisition
transactions.

  2.   Deemed Issuance of Additional Common Shares. The shares of common stock
ultimately Issuable upon exercise of an Option (including the shares of common
stock ultimately Issuable upon conversion or exercise of a Convertible Security
Issuable pursuant to an Option) are deemed to be Issued when the Option is
Issued. The shares of common stock ultimately Issuable upon conversion or
exercise of a Convertible Security (other than a Convertible Security Issued
pursuant to an Option) shall be deemed Issued upon Issuance of the Convertible
Security. The maximum amount of common stock Issuable is determined without
regard to any future adjustments permitted under the instrument creating the
Options or Convertible Securities.
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Greyrock Capital                                          Antidilution Agreement
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  3.   Adjustment of Warrant Price for Diluting Issuances.

  3.1  Weighted Average Adjustment. If the Company Issues Additional Common
Shares after the date of the Warrant and the consideration per Additional Common
Share (determined pursuant to Section 9) is less than the Warrant Price in
effect immediately before such Issue, the Warrant Price in effect immediately
before such Issue shall be reduced, concurrently with such Issue, to a price
(calculated to the nearest hundredth of a cent) determined by multiplying the
Warrant Price by a fraction:

  (a)  the numerator of which is the amount of common stock outstanding
immediately before such Issue plus the amount of common stock that the aggregate
consideration received by the Company for the Additional Common Shares would
purchase at the Warrant Price in effect immediately before such Issue, and

  (b)  the denominator of which is the amount of common stock outstanding
immediately before such Issue plus the number of such Additional Common Shares.

  3.2  Adjustment of Number of Shares. Upon each adjustment of the Warrant
Price, the number of Shares issuable upon exercise of the Warrant shall be
increased to equal the quotient obtained by dividing (a) the product resulting
from multiplying (i) the number of Shares issuable upon exercise of the Warrant
and (ii) the Warrant Price, in each case as in effect immediately before such
adjustment, by (b) the adjusted Warrant Price.

  3.3  Securities Deemed Outstanding. For the purpose of this Section 3, all
securities issuable upon exercise of any outstanding Convertible Securities or
Options, warrants, or other rights to acquire securities of the Company shall be
deemed to be outstanding.

  4.   No Adjustment for Issuances Following Deemed Issuances. No adjustment to
the Warrant Price shall be made upon the exercise of Options or conversion of
Convertible Securities.

  5.   Adjustment Following Changes in Terms of Options or Convertible
Securities. If the consideration payable to, or the amount of common stock
Issuable by, the Company increases or decreases, respectively, pursuant to the
terms of any outstanding Options or Convertible Securities, the Warrant Price
shall be recomputed to reflect such increase or decrease. The recomputation
shall be made as of the time of the Issuance of the Options or Convertible
Securities. Any changes in the Warrant Price that occurred after such Issuance
because other Additional Common Shares were Issued or deemed Issued shall also
be recomputed.

  6.   Recomputation Upon Expiration of Options or Convertible Securities. The
Warrant Price computed upon the original Issue of any Options or Convertible
Securities, and any subsequent adjustments based thereon, shall be recomputed
when any Options or rights of conversion under Convertible Securities expire
without having been exercised. In the case of Convertible Securities or Options
for common stock, the Warrant Price shall be recomputed as if the only
Additional Common Shares Issued were the shares of common stock actually Issued
upon the exercise of such securities, if any, and as if the only consideration
received therefor was the consideration actually received upon the Issue,
exercise or conversion of the Options or Convertible Securities. In the case of
Options for Convertible Securities, the Warrant Price shall be recomputed as if
the only Convertible Securities Issued were the Convertible Securities actually
Issued upon the exercise thereof, if any, and as if the only consideration
received therefor was the consideration actually received by the Company
(determined pursuant to Section 9), if any, upon the Issue of the Options for
the Convertible Securities.

  7.   Limit on Readjustments. No readjustment of the Warrant Price pursuant to
Sections 5 or 6 shall increase the Warrant Price more than the amount of any
decrease made in respect of the Issue of any Options or Convertible Securities.

  8.   30 Day Options. In the case of any Options that expire by their terms not
more than 30 days after the date of Issue thereof, no adjustment of the Warrant
Price shall be made until the expiration or exercise of all such Options.

  9.   Computation of Consideration. The consideration received by the Company
for the Issue of any Additional Common Shares shall be computed as follows:

  (a)  Cash shall be valued at the amount of cash received by the Corporation,
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excluding amounts paid or payable for accrued interest or accrued dividends.

  (b)  Property.  Property other than cash shall be computed at the fair market
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value thereof at the time of the Issue as determined in good faith by the Board
of Directors of the Company.

  (c)  Mixed Consideration.  The consideration for Additional common Shares
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Issued together with other property of the Company for consideration that covers
both shall be determined in good faith by the Board of Directors.

  (d)  Options and Convertible Securities.  The consideration per Additional
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Common Share for Options and Convertible Securities shall be determined by
dividing:

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

  (ii) the maximum amount of common stock (as set forth in the instruments
relating thereto, without regard to any provision contained therein for a
subsequent adjustment of such number) ultimately Issuable upon the exercise of
such Options or the conversion of such Convertible Securities.

  10.  General.

  10.1 Governing Law. This Antidilution Agreement shall be governed in all
respects by the laws of the State of California as such laws are applied to
agreements between California residents entered into and to be performed
entirely within California.
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Greyrock Capital                                          Antidilution Agreement
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  10.2 Successors and Assigns. Except as otherwise expressly provided herein,
the provisions hereof shall inure to the benefit of, and be binding upon, the
successors, assigns, heirs, executors and administrators of the parties hereto.

  10.3 Entire Agreement. This Antidilution Agreement and the other documents
delivered pursuant and otherwise relating hereto constitute the full and entire
understanding and agreement between the parties with regard to the subjects
hereof and thereof. The terms and provisions of this Agreement may not be waived
or amended, except in a writing executed by Company and a duly authorized
officer of Holder.

  10.4 Notices. etc. All notices and other communications required or permitted
hereunder shall be in writing and shall be mailed by first class mail, postage
prepaid, certified or registered mail, return receipt requested, addressed (a)
if to Purchaser at Purchaser's address as set forth in the heading to this
Agreement, or at such other address as Purchaser shall have furnished to the
Company in writing, or (b) if to the Company, at the Company's address set forth
in the heading to this Agreement, or at such other address as the Company shall
have furnished to the Purchaser in writing.

  10.5 Severability. In case any provision of this Antidilution Agreement shall
be invalid, illegal, or unenforceable, the validity, legality and enforceability
of the remaining provisions of this Antidilution Agreement shall not in any way
be affected or impaired thereby.

  10.6 Titles and Subtitles. The titles of the sections and subsections of this
Agreement are for convenience of reference only and are not to be considered in
construing this Antidilution Agreement.

  10.7 Counterparts. This Antidilution Agreement may be executed in any number
of counterparts, each of which shall be an original, but all of which together
shall constitute one instrument.

  Company:

     P-COM, INC.


     By /s/ Karl F. Meyer
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        Vice President, Corporate Controller


  Purchaser:

     GREYROCK CAPITAL


     By /s/ Lisa Nagano
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     Title Senior Vice President
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