PROMISSORY NOTE

$125,000                                                      September 11, 1997


                  FOR VALUE RECEIVED, WORLDPORT COMMUNICATIONS, INC., a Delaware
corporation  (together  with  its  successors and  assigns,   herein  called the
"Debtor"),  promises to pay to Cablex  Electronique,  Ltd., or its successors or
assigns  (herein  called  the  "Holder"),  the  principal  sum  of  ONE  HUNDRED
TWENTY-FIVE  THOUSAND  AND 00/100  DOLLARS  ($125,000),  together  with  accrued
interest on the unpaid principal hereof at a rate of 10% per annum from the date
hereof, subject to the terms and conditions set forth herein.

                  The Debtor shall pay all outstanding  principal due under this
Note and all  accrued  and unpaid  interest  no later than  December  31,  1997.
Following  such date,  the interest  rate on any unpaid  principal  and interest
hereunder shall accrue at a rate of 15% per annum until paid in full.

                  The  advances  represented  by this  Promissory  Note are made
pursuant to an up to $5,000,000  bridge  financing  arrangement  through  Maroon
Bells  Capital  Partners,  Inc.  (the  "Bridge  Financing").  Payments  of  both
principal  and  interest  under  this  Promissory  Note (as  amended,  modified,
refinanced or refunded in whole or in part from time to time, herein called this
"Note") are to be made c/o Maroon Bells Capital  Partners,  Inc. 100  California
Street,  Suite 1160, San Francisco,  California 94111, or at such other place as
the Holder shall  designate in writing,  in lawful money of the United States of
America.

                  The Debtor represents and warrants to the Holder that: (i) the
Debtor is a  corporation  duly formed,  validly  existing,  and in good standing
under the laws of Delaware; (ii) the execution, delivery, and performance by the
Debtor of this Note have been duly authorized by all necessary  corporate action
and do not and will not (A) contravene the Debtor's Articles of Incorporation or
Bylaws;  (B) violate or cause a breach or default of any  provision  of any law,
rule, regulation,  order, writ, judgment,  injunction,  decree, determination or
award  applicable  to the  Debtor;  or (C)  violate  or result in a breach of or
constitute  a default  under any  indenture  or loan or credit  agreement or any
other agreement, lease, or instrument to which the Debtor is a party or by which
it or its properties may be bound or affected; and (iii) this Note is the legal,
valid, and binding  obligation of the Debtor  enforceable  against the Debtor in
accordance  with its terms,  except to the exteny that such  enforcement  may be
limited by applicable bankruptcy,  insolvency,  and other similar laws affecting
creditors' rights generally and principles of equity.

                  So long as any  amount of  principal  or  interest  under this
Note  shall  remain  unpaid or  outstanding,  except as  otherwise  agreed to in
writing by Holder:  (i) the Debtor will  preserve  and  maintain  its  corporate
existence and good standing in the  jurisdiction of its formation;  and (ii) the
Debtor will  conduct its  businesses  and  operations  only in, and not take any


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action except in, the ordinary course of business consistent with past practice,
including,  but not limited to, the  following:  (A) not make any payment of any
distribution to any shareholder,  or otherwise redeem or acquire any shareholder
interest; (B) not sell, lease or otherwise dispose of or agree to sell, lease or
otherwise dispose of, any assets,  properties,  rights or claims,  except in the
ordinary  course of  business  and at prices and on terms  consistent  with past
practice;  or (C) not incur or become  subject  to, nor agree to incur or become
subject to, any debt, obligation or liability,  contingent or otherwise,  except
additional borrowings under the Bridge Financing, and current liabilities in the
ordinary course of business, consistent with past practice.

                  Debtor shall have the right to prepay this Note in whole or in
part at any time, without penalty or premium.

                  Debtor  hereby  waives  diligence,   presentment,  demand  for
payment, protest and notice of any kind whatsoever in connection with this Note,
now or hereafter required by applicable law.

                  The Holder  shall have the right to convert all or any portion
of  the  outstanding  principal  and  interest  payable  hereunder  into  equity
interests in Debtor on terms acceptable to Debtor and the Holder. Debtor and the
Holder agree to negotiate in good faith with respect to such conversion rights.

                  Debtor hereby agrees to pay all of Holder's costs and expenses
related to this Note, and the related documents and  transactions,  upon demand.
Debtor  hereby  agrees  to pay all  costs of  collection,  including  reasonable
attorneys'  fees and all costs of suit incurred by Holder in any  proceeding for
the collection of the debt evidenced hereby, or in any litigation or controversy
arising from or connected with this Note.

                  This Note may not be changed orally,  but only by an agreement
in writing,  signed by the party against whom enforcement of any waiver, change,
modification or discharge is sought.

                  This Note  shall  bind and inure to the  benefit of Debtor and
Holder and their respective executors,  administrators,  legal  representatives,
heirs, distributees, legatees, successors and assigns.

                  This Note shall be governed  by and  construed  in  accordance
with the internal laws of the State of Delaware. 

                  IN WITNESS WHEREOF,  Debtor has signed and delivered this Note
as of the day and year first above written.


                                            WORLDPORT COMMUNICATIONS, INC.



                                            By:     /s/  W. Dean Spies

                                            Name:    W. Dean Spies              

                                            Title:      Chief Financial Officer