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                                                                    EXHIBIT 99.7


                                  BILL OF SALE



Seller:   Ambix Systems Corp.                      February 6, 1996
          400 West Avenue
          Rochester, NY 14611


Buyer:    ACC Corp.
          400 West Avenue
          Rochester, NY 14611
 
 
Hardware and software modifications to
configure the Ambix rates to the ACC
UK Long Distance Ltd. billing systems.             $221,000
 
Ambix "Net Ops" Application, Version 1.0,
release 1.0.                                       $310,470
 
Software modifications to configure the
Ambix rates for RIT call processing, and
RIT call processing system (Version 1.0,
Release 1.0, modification level 0).                $176,000
 
Ambix "AIA" Intermediation System (Version 2.0,
Release 1.3, modification level 2).                $ 65,000
                                                   --------
 
TOTAL                                              $772,470
                                                   ========
 

Acknowledgement:  Seller, Ambix Systems Corp., a New York corporation, having
its principal place of business at 400 West Avenue, Rochester, NY 14611, in
consideration of the above amounts, does hereby sell, assign, and transfer to
Buyer, ACC Corp., the indefinite right to use the above property (Object code
only) the Seller further acknowledges that all amounts due Seller from the Buyer
related to the above have been received prior to December 31, 1995.  Buyer
acknowledges that the above object code and related systems have substantially
met the conditions for approval and acceptance for their intended use by Buyer
subject to the terms of acceptance set forth in Section 13 of a Software License
Agreement between each company dated on or about February 6, 1996.

ATTEST:

/s/ Andrew McIntosh                 /s/ David K. Laniak
-------------------------           -----------------------
Andrew McIntosh, President          David K. Laniak
Ambix Systems Corp.                 Chief Executive Officer
                                    ACC Corp.
