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                                                               EXHIBIT 2.3


                  SECOND AMENDMENT TO STOCK PURCHASE AGREEMENT


         THIS SECOND AMENDMENT (the "Amendment") to the STOCK PURCHASE AGREEMENT
dated as of August 22, 1997, as amended by a first Amendment dated October 31,
1997 (together, the "Agreement"), is entered into as of the 27th day of
February, 1998 by and among MCC ACQUISITION CORP. ("MCCAC"), PRIORITY
INTERNATIONAL COMMUNICATIONS, INC. ("PIC") and WAYNE WRIGHT and BONNER HARDEGREE
as the majority shareholders of PIC (the "PIC Majority Shareholders").

                                     RECITAL

         MCCAC, PIC and the PIC Majority Shareholders mutually desire to amend
the Agreement in the manner set forth in this Amendment and to make certain
other agreements.

                                   AGREEMENTS

         In consideration of the recital and the agreements set forth in the
Agreement as amended hereby, the parties agree:

         1. The Short-Term Note, as defined in the Agreement, is amended and
restated in the form attached hereto.

         2. All references to the Short-Term Note in the Agreement (and any
documents or instruments executed and delivered in connection with the
Agreement) shall refer to the Short-Term Note as amended and restated as of the
date hereof. Upon receipt of the Amended and Restated Promissory Note
(Short-Term Note), duly executed by MCCAC, the PIC Majority Shareholders shall
return the original Short-Term Note to MCCAC for cancellation.

         3. Section 1.3 of the Agreement is amended to read in its entirety as
follows:

            1.3 Special Default Right. The Short-Term Note is payable in
         full on June 30, 1998. If the Short-Term Note is not paid in full on
         June 30, 1998, the PIC Majority Shareholders shall have the right,
         subject to the conditions described herein, to rescind the transactions
         contemplated by this Agreement, retaining the $500,000.00 payable
         pursuant to Section 1.1(a) of this Agreement as liquidated damages (the
         "PIC Rescission Right"). The PIC Majority Shareholders may only
         exercise the PIC Rescission Right during the 30-day period beginning on
         June 30, 1998 and only if the PICR 



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         Shareholders have exercised the PICR Rescission Right described in
         Section 1.4 of the Stock Purchase Agreement dated August 22, 1997, as
         amended by a First Amendment dated October 31, 1997 and a Second
         Amendment dated February 27, 1998, to which MCCAC, PIC Resources Corp,
         the shareholders of PIC Resources Corp and ATN Communications, Inc. are
         parties. If the PIC Rescission Right and the PICR Rescission Right are
         exercised, such action shall be the sole remedy for MCCAC's failure to
         pay the Short-Term Note in full and MCCAC, the Murdock Communications
         Corporation, PIC and the PIC Shareholders shall be fully released from
         all obligations and liabilities under the Agreement and all agreements
         and instruments delivered pursuant to the Agreement.

         4. MCCAC agrees to pay Wayne Wright ("Wright") $166,412.00, plus
interest at the rate of twelve percent (12.0%) per annum on such amount from
February 1, 1998 until paid, on or prior to February 27, 1998, representing the
payment which was scheduled to be made, on January 31, 1998, to Wright by MCCAC
under the Long-Term Note dated October 29, 1997. Upon receipt of such payment,
Wright waives any and all rights and remedies he may have against MCCAC, its
shareholders, officers or directors, with respect to the failure of MCCAC to
timely make such payment.

         5. MCCAC agrees to pay Bonner Hardegree ("Hardegree") $20,949.00 plus
interest at the rate of twelve percent (12.0%) per annum on such amount from
February 1, 1998 until paid, on or prior to February 27, 1998, representing the
payment which was scheduled to be made, on January 31, 1998, to Hardegree by
MCCAC under the Long-Term Note dated October 29, 1997. Upon receipt of such
payment, Hardegree waives any and all rights and remedies he may have against
MCCAC, its shareholders, officers or directors, with respect to the failure of
MCCAC to timely make such payment.

         6. From and after the date hereof and until the Long-Term Notes are
paid in full, MCCAC agrees that it will take no action to remove either
Hardegree or Wright from office as an officer or director of either PIC or PIC
Resources Corp. or ATN Communications, Inc. or to materially or substantially
restrict their presently assigned duties and responsibilities unless they commit
acts constituting fraud or felony to MCCAC, PIC or PIC Resources Corp., make
material misrepresentations to the officers or directors of MCCAC or materially
disregard their duties under such offices.

         7. MCCAC hereby releases PIC, Wright and Hardegree from any and all
liability to MCCAC which may accrue or arise under the Agreement or the closing
of the transaction contemplated by the Agreement which is alleged to 


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result from the inaccuracy or incompleteness of any of the financial statements,
proforma income or performance projections or other financial information
concerning PIC, PIC Resources Corp. or ATN Communication, Inc. furnished to
MCCAC prior to closing.

         8. Except as amended by this Amendment, the Agreement remains in
effect, unchanged and binding upon the parties thereto. All references to the
Agreement in documents or instruments executed and delivered by the parties in
connection with the Agreement shall be deemed to refer to the Agreement as
amended hereby.

                                             MCC ACQUISITION CORP.

                                             By:  Guy O. Murdock
                                                  ---------------------------- 
                                                  Guy O. Murdock, Chairman of
                                                             the Board

                                             PRIORITY INTERNATIONAL
                                             COMMUNICATIONS, INC.

                                             By: /s/ Bonner B. Hardegree
                                                -------------------------------
                                                Bonner B. Hardegree, Vice 
                                                President


                                             PIC MAJORITY SHAREHOLDERS

                                             /s/ Wayne Wright
                                             ---------------------------------
                                             WAYNE WRIGHT

                                             /s/ Bonner Hardegree
                                             --------------------------------- 
                                             BONNER HARDEGREE




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