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                                                               EXHIBIT 10.10(f)



                                AMENDMENT NO. 6

         AMENDMENT NO. 6, dated as of December 23, 1998 (this "Agreement"), by
and among WORLDPORT INTERNATIONAL, INC., a Delaware corporation (the
"Company"), WORLDPORT COMMUNICATIONS, INC., a Delaware corporation (the
"Parent"), the Lenders (as defined in the Credit Agreement) which are a party
hereto (including Bankers Trust Corporation, in its individual capacity) and
BANKERS TRUST COMPANY, as Administrative Agent (in such capacity, the "Agent")
and Collateral Agent (in such capacity, the "Collateral Agent") and as joint
creditor with the other Lenders under the Credit Agreement, each as defined
below.

                              W I T N E S S E T H:

         WHEREAS, the Company and the Parent are parties to a Credit Agreement
dated as of June 23, 1998 (as in effect, the "Credit Agreement") with the
Lenders, the Agent and the Collateral Agent;

         WHEREAS, the Company and the Parent have agreed to raise a certain
amount of capital pursuant to, and in accordance with, the terms set forth in
the Credit Agreement by December 23, 1998 (the "Target Date");

         WHEREAS, the Parent and the Company have requested that the Agent and
the Lenders extend the Target Date to December 29, 1998;

         NOW THEREFORE, in consideration of the foregoing premises and for
other good and valuable consideration, the sufficiency of which is hereby
acknowledged, the parties hereto agree to the following:

         1.       Defined Terms. Capitalized terms used but not otherwise 
defined herein shall have the respective meanings ascribed thereto in the
Credit Agreement.
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         2.       Amendment. Section 5.16(d) of the Credit Agreement is amended
by deleting the reference to the date "December 23, 1998" appearing therein and
substituting the date "December 29, 1998" therefor.

         3.       Applicable Law; Submission to Jurisdiction. THIS AGREEMENT 
SHALL BE CONSTRUED IN ACCORDANCE WITH AND GOVERNED BY THE LAWS OF THE STATE OF
NEW YORK.

         4.       No Novation. This Agreement shall not extinguish the 
obligations for the payment of money outstanding under the Credit Agreement or
any Note or discharge or release the Lien or priority of any security
agreement, any pledge agreement or any other security therefor or discharge any
obligation under any guaranty. Nothing herein contained shall be construed as a
substitution or novation of the Obligations outstanding under the Credit
Agreement or instruments securing the same, which shall remain in full force
and effect, except as modified hereby or by instruments executed concurrently
herewith. Nothing expressed or implied in this Agreement, the Credit Agreement,
or any other document contemplated hereby or thereby shall be construed as a
release or other discharge of the Company, the Parent or any Guarantor under
the Credit Agreement or any Pledgor or Grantor under any Security Document from
any of its obligations and liabilities as a "Company", "Parent", "Guarantor",
"Pledgor" or "Grantor" under the Credit Agreement or the Security Documents or
any other Finance Document. Whenever the term "Credit Agreement" is used in any
of the Finance Documents it shall mean and refer to the Credit Agreement as
modified pursuant hereto. Each of the Credit Agreement and the other Finance
Documents shall remain in full force and effect, except as expressly modified
hereby.

         5.       Counterparts. This Agreement may be executed in two or more
counterparts, each of which shall constitute an original but all of which when
taken together shall constitute but one contract.

         6.       Headings. The headings of this Agreement are for convenience
of reference only, are not part of this Agreement and are not to affect the
construction of, or to be taken into consideration in interpreting, this
Agreement.



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         7.       Effectiveness. This Agreement shall become effective as of
the date when copies hereof which, when taken together, bear the signatures of
each of the Company, the Parent, the Agent, the Collateral Agent and the
Majority Lenders have been received by the Agent.

         8.       Payment of Expenses. In furtherance of the provisions of 
Section 9.1 of the Credit Agreement, the Parent and Company shall jointly and
severally, whether or not the transactions hereby contemplated are consummated,
upon demand of the Agent pay all reasonable out-of-pocket costs (including
legal fees), charges and expenses of the Agent and Collateral Agent in
connection with the negotiation, preparation, execution and delivery of this
Agreement and the documents and instruments referred to herein, and otherwise
reviewed in connection herewith and therewith.



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         IN WITNESS WHEREOF, the parties hereto have caused this Agreement to
be duly executed by their duly authorized officers, all as of the date and year
first above written.


                                   WORLDPORT INTERNATIONAL, INC.



                                   by
                                      -----------------------------------------
                                      Name:
                                      Title:


                                   WORLDPORT COMMUNICATIONS, INC.



                                   by
                                     ------------------------------------------
                                     Name:
                                     Title:
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                                   BANKERS TRUST COMPANY

                                   as Agent and Collateral Agent



                                   by
                                      -----------------------------------------
                                      Name:
                                      Title:


                                   BANKERS TRUST CORPORATION

                                   as Lender



                                   by
                                      -----------------------------------------
                                      Name:
                                      Title:



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                                    DREYFUS PREMIER LIMITED TERM HIGH 
                                    INCOME FUND



                                    by
                                      -----------------------------------------
                                      Name:
                                      Title:



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