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                                                                   EXHIBIT 10.4



                                Arris Group, Inc.
                             11450 Technology Circle
                              Duluth, Georgia 30097

                                 March 11, 2003

Nortel Networks Inc.
221 Lakeside Boulevard
Richardson, Texas  75082-4399

Ladies and Gentlemen:

         This letter memorializes certain agreements that we have reached with
respect to the Registration Rights Agreement by and between Nortel Networks Inc.
("Investor"), as successor in interest to Nortel Networks LLC (which was merged
with and into Nortel as of December 31, 2002), and Arris Group, Inc. ("Newco")
dated as of August 3, 2001 (the "Agreement").

         We have agreed that:

(1)      the limitations contained in Subsections 4(b) and (c) of the Agreement
         shall not apply to any shares of Common Stock of Newco loaned pursuant
         to the Master Securities Loan Agreement by and between Investor and
         CIBC World Markets Corp. dated as of March 11, 2003 (the "Loan
         Agreement"), and any substitutes therefor that are returned in lieu
         thereof pursuant to the Loan Agreement (collectively, the "Covered
         Shares");

(2)      any shares that are returned pursuant to the Loan Agreement shall
         constitute "Registrable Shares" for purposes of the Agreement;

(3)      the Stockholders (as defined in the Agreement) shall be entitled to
         have the Covered Shares registered or reregistered, as the case may be,
         including more than once. It is understood that all of the provisions
         of the Agreement shall apply to the registration of the Covered Shares;
         and

(4)      notwithstanding the limitation contained in Subsection 4(b) of the
         Agreement, if at any time the residual Registrable Shares held by
         Investor is less than 5% of the then outstanding shares of Common Stock
         of Newco, Investor shall be entitled to cause Newco to effect a single
         registration under Section 1 of the Agreement of all (but not less than
         all) of the residual Registrable Shares, provided that Investor is not
         then entitled to sell the entire amount of residual Registrable Shares
         pursuant to Rule 144(e)(1) promulgated under the Securities Act of
         1933, as amended.

         In addition to the foregoing agreements, Newco acknowledges that the
transactions contemplated under the Loan Agreement are not inconsistent with the
Second Amended and Restated Investor Rights Agreement, dated as of June 7, 2002
(the "Investor Rights Agreement"), and that Investor shall be deemed to
"Beneficially Own" (as defined in the Investor Rights Agreement) the Covered
Shares for purposes of the Investor Rights Agreement while such shares are
loaned under the Loan Agreement.


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         Newco also agrees to reimburse Investor for legal fees and expenses of
outside counsel to Investor in connection with the negotiation of the Loan
Agreement; provided, however, that Newco shall not be liable for aggregate fees
and expenses in excess of $5,000.

         If the foregoing accurately reflects our agreements, please sign where
indicated below.

                                      Sincerely yours,

                                      Arris Group, Inc.


                                      By:
                                         --------------------------------------
                                           Lawrence Margolis
                                           Executive Vice President



Agreed to:

Nortel Networks Inc.

By:
   ---------------------------------
Its:
    --------------------------------


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