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                                                                     EXHIBIT 2.6

                  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 that First Amendment to Stock
Purchase Agreement dated as of the 29th day of October, 1997 (the "Agreement")
is entered into as of the 27th day of February, 1998, by and among MCC
ACQUISITION CORP. ("MCCAC"), PIC RESOURCES CORP. ("PICR"), WAYNE WRIGHT and
BONNER HARDEGREE as the only shareholders of PICR (the "PICR Shareholders") and
ATN COMMUNICATIONS, INC., a wholly-owned subsidiary of PICR ("ATN").

                                     RECITAL

         MCCAC, PICR, the Shareholders and ATN mutually desire to amend the
Agreement in this Amendment.

                                   AGREEMENTS

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

         1. A new Section 1.4 is added to the Agreement to read in its entirety
as follows:

             1.4 Special Default Right. Pursuant to a Stock Purchase Agreement
         dated August 22, 1997, as amended by a First Amendment dated October
         29, 1997 and a Second Amendment dated February 27, 1998 (the "PICR
         Purchase Agreement"), MCCAC will issue and deliver its "Short-Term
         Note" (as defined in the PIC Purchase Agreement) to the shareholders of
         Priority International Communications, Inc. ("PIC"). 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 in Section 1.3 of the
         PIC Purchase Agreement, to rescind the transactions contemplated by the
         PIC Purchase Agreement, retaining the $500,000.00 payable pursuant to
         Section 1.1(a) of the PIC Purchase Agreement as liquidated damages (the
         "PIC Rescission Right"). If the PIC Rescission Right is exercised by
         the PIC Majority Shareholders, the PICR Shareholders shall also have
         the right, exercisable during the 30-day period beginning on June 30,
         1998, and subject to the provisions of this Section 1.4, to rescind the
         transactions contemplated by this Agreement, retaining the $30,000.00
         payable 


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         pursuant to Section 1.1(a) of this Agreement, and the $400,000.00
         advanced to Wayne Wright by Guy Murdock (the "Wright Note") in
         connection with the acquisition of ATN, which obligation was assumed by
         PICR and assigned by Guy Murdock to Murdock Communications Corporation
         ("Murdock"), as liquidated damages. 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, PICR
         shall be released from any obligation under the Wright Note, MCCAC,
         Murdock and the PICR Shareholders shall be fully released from all
         obligations under this Agreement and all agreements and instruments
         delivered pursuant to this Agreement and the PICR Shareholders shall
         surrender to Murdock for cancellation any shares of Murdock common
         stock issued to the PICR Shareholders pursuant to this Agreement.

         2. MCCAC hereby releases PICR, ATN and the PICR Shareholders 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
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.

         3. From and after the date hereof and until the Long-Term Notes (as
defined in the PIC Purchase Agreement) 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.

         4. Except as amended by this Amendment, the Agreement remains in
effect, unchanged and binding upon the parties thereto.

                                              MCC ACQUISITION CORP.

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


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                                                     PIC RESOURCES CORP.

                                                     By:  /s/ Wayne Wright
                                                         -----------------------
                                                         Wayne Wright, President


                                                     PICR MAJORITY SHAREHOLDERS:

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

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


                                                     ATN COMMUNICATIONS, INC.

                                                     By:  /s/ Wayne Wright
                                                         -----------------------
                                                         Wayne Wright, President



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