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                                                                   Exhibit 10.25

January 20, 2003

Via Facsimile

Mr. Stuart P. Dawley, Secretary
AirNet Communications Corporation
3950 Dow Road
Melbourne, Florida 32934

Re:   Conversion and Exchange of Series B Convertible Preferred Stock

Dear Mr. Dawley:

Pursuant to our letter to Mr. John Igoe dated January 20, 2003 and Section 6(a)
of the Series B Convertible Preferred Stock Certificate of Designation of AirNet
Communications Corporation (the "Company"), the undersigned, the holder of
certificate A B001 for 318,471.33 shares of Series B Convertible Preferred
Stock, $.01 par value ("Series B Preferred Stock"), of the Company, hereby
irrevocably elects to convert and exchange all such Series B Preferred Stock in
consideration of payment by the Company to Mellon Ventures, L.P. ("Mellon") of
U.S. $500,000 and requests the issuance of 6,369,427 shares of the Company's
common stock, $.001 par value ("Common Stock"), and payment of the fair market
value of .3 share of Common Stock. Subject to the closing of the contemplated
transaction, the Common Stock Purchase Warrant dated May 15, 2001 for the
purchase of up to 955,414 shares of AirNet Common Stock is hereby terminated.

We hereby request that the certificate or certificates for such shares be
issued, at the closing of a contemplated financing of the Company in the amount
of at least U.S.$16,000,000.00, in the name of Mellon Ventures, L.P., whose
address is c/o Mellon Ventures, Inc., One Mellon Center, Suite 5210 Pittsburgh,
PA 15258, or such other person or persons in the amount or amounts as we shall
designate in writing to the Company.

Certificate A B001 is enclosed for cancellation.

Very truly yours,                              Accepted and Agreed:

Mellon Ventures, L.P.                          AirNet Communications Corporation

By: MVMA, LP, its General Partner

By: MVMA, Inc., its General Partner

/s/ Paul D. Cohn                               /s/ Stuart P. Dawley
-------------------------------------          ---------------------------------
Name: Paul D. Cohn                             Name: Stuart P. Dawley
     --------------------------------               ----------------------------
Title: Partner                                 Title: V.P. & General Counsel
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Enclosure

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January 20, 2003

Via Facsimile

John G. Igoe, Esq.
Edwards & Angell, LLP
One North Clematis Street, Suite 400
West Palm Beach, Florida 33401

Re:   AirNet Communications Corporation

Dear Mr. Igoe:

With reference to our letter to Mr. Dawley, Secretary of AirNet Communications
Corporation (the "Company"), dated January 20, 2003 providing notice of election
to convert and exchange 318,471.33 shares of the Company's Series B Convertible
Preferred Stock, $.01 par value, and the subsequent issuance of 6,369,427 shares
of the Company's common stock, $.001 par value, (the "Conversion Letter") to
Mellon Ventures, L.P. or its designee or designees ("Mellon"), we understand
that you shall hold such Conversion Letter and certificate A B001 enclosed
therewith (together with the Conversion Letter, the "Escrowed Documents") in
escrow pursuant to the terms and conditions set forth in the attached Escrow
Agreement and deliver the Escrowed Documents to the Company at the closing of a
contemplated corporate financing of at least U.S.$16,000,000.00 by TECORE, Inc.
and SCP Private Equity Partners II, L.P., or affiliates thereof (the "Proposed
Transaction").

If the Proposed Transaction has not closed by 5:00 p.m. EST, Wednesday, April
30, 2003, you are hereby instructed to immediately return the Escrowed Documents
to the undersigned.

Please signify your acceptance of, and agreement with, the foregoing by signing
below.

Very truly yours,                                    Accepted and Agreed:

Mellon Ventures, L.P.                                Edwards & Angell, LLP

By: MVMA, LP, its General Partner

By: MVMA, Inc., its General Partner

/s/ Paul D. Cohn                               /s/ John G. Igoe, P.A.
-------------------------------------          ---------------------------------
Name: Paul D. Cohn                             Name: John G. Igoe, P.A.
     --------------------------------               ----------------------------
Title: Partner                                 Title: Partner
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