THE TRANSFER OF THIS NOTE IS RESTRICTED.  SEE SECTION 12 HEREIN.



                           SECOND AMENDED AND RESTATED
                         SENIOR SECURED PROMISSORY NOTE

$850,000.00                                                       June 20, 1997
                                                                   Dallas, Texas

1.  Agreement  to Pay.  FOR  VALUE  RECEIVED,  the  receipt  of which is  hereby
acknowledged,  the undersigned,  Telenational  Communications,  Inc., a Delaware
corporation ("TCI") and WorldPort Communications,  Inc. ("WorldPort") (WorldPort
and TCI shall  hereinafter be referred to collectively as the "Maker"),  promise
to pay, as joint and several obligors,  to the order of VALUE PARTNERS,  LTD., a
Texas limited  partnership,  (hereinafter  referred to as the "Payee", and Payee
and each successive  owner and holder of this Note being  hereinafter  generally
referred to as the "Holder") in the manner  provided for herein of the principal
sum of

               EIGHT HUNDRED FIFTY THOUSAND AND NO/100 DOLLARS
                                 ($850,000.00)

together with interest on the  outstanding  principal  balance hereof  remaining
from time to time  unpaid at the rate  provided  in Section 2 hereof.  This Note
reinstates,  amends,  renews,  restates and replaces,  according to all terms as
modified  herein,  that certain Amended and Restated  Senior Secured  Promissory
Note in the  principal  balance  of $  850,000.00  dated  as of March  20,  1997
executed by Telenational  Communications Limited Partnership, a Nebraska limited
partnership  ("Telenational") in favor of Payee (the ATelenational Note@), which
Telenational  Note  reinstated,  amended,  renewed,  restated and replaced  that
certain  Unsecured  Senior  Promissory  Note dated as of  November  8, 1995 (the
"Prior Note")  originally  payable by  Telenational to ADEN  ENTERPRISES,  INC.,
(hereinafter referred to as AAden@) which Prior Note was assigned and pledged by
Aden to Payee and  acquired  at public sale by Payee  pursuant  to that  certain
Amended and Restated Pledge Agreement dated as of December 8, 1995. This Note is
entitled to all of the liens, benefits, priorities, rights and privileges of the
Prior Note and the Telenational Note, and related loan documents, including that
certain  Pledge and  Security  Agreement  dated  March 20,  1997 by and  between
Telenational and Value (the  ATelenational  Pledge  Agreement@) and that certain
Loan Modification Agreement dated March 20, 1997 by and between Telenational and
Payee,  which are hereby  ratified and carried forward in full force and effect,
as  modified  herein,  in the Pledge  Agreement  and in the Loan  Agreement,  as
defined herein.  Contemporaneous  with the date hereof,  Maker and the Payee are
entering into that certain First Amended Loan Modification  Agreement (the ALoan
Agreement@).

2.    Interest Rate.

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                  SECOND AMENDED AND RESTATED SENIOR SECURED
                            PROMISSORY NOTE, PAGE 1
<PAGE>

      (a) The outstanding principal balance hereof shall bear simple interest at
the rate of the lesser of fifteen  percent (15%) per annum through and including
June 19, 1997 or the Highest Lawful Rate, as defined herein, and commencing June
20, 1997,  the lesser of fourteen  percent (14%) per annum or the Highest Lawful
Rate, as defined herein (the "Regular  Rate"),  computed daily on the basis of a
360 day year  consisting of twelve 30-day months for each day all or any part of
the principal  balance hereof shall remain  outstanding,  but to the extent such
computation  of interest  might cause the rate of interest which this Note bears
to exceed the Highest Lawful Rate,  such interest shall be computed on the basis
of a three hundred  sixty-five (365) day or a three hundred  sixty-six (366) day
year, as the case may be. If any installment of principal and/or interest is not
paid on or before  ten (10) days  following  the date it is due or if the entire
unpaid  principal  balance and accrued unpaid  interest is not paid on or before
the  earlier  to occur of the Final  Maturity  Date,  as defined  below,  or any
acceleration  of payment  permitted  hereby,  all  unpaid  amounts of this Note,
including  principal and interest,  shall  thereafter  bear simple interest at a
default rate of the lesser of seventeen  percent ( 17%) per annum or the Highest
Lawful Rate as defined herein .


      (b) "Highest  Lawful Rate" shall mean at the  particular  time in question
the  maximum  rate of  interest  which,  under  Applicable  Law,  Payee  is then
permitted to charge Maker on this Note. "Applicable Law" shall mean (i) the laws
of the United States of America applicable to contracts made or performed in the
State  of  Texas,  now or at any time  hereafter  prescribing  maximum  rates of
interest or  eliminating  maximum  rates of interest on loans and  extensions of
credit,  (ii) the laws of the  State of  Texas  including,  without  limitation,
Article 5069-1.04 of the Texas Revised Civil Statutes Annotated, as the same may
be amended  from time to time  ("Article  1.04"),  now or at any time  hereafter
prescribing or eliminating  maximum rates of interest on loans and extensions of
credit,  and (iii) any other laws at any time  applicable  to contracts  made or
performed  in the State of Texas which  permit a higher  interest  rate  ceiling
hereunder. If the maximum rate of interest which, under Applicable Law, Payee is
permitted to charge  Maker on this Note shall change after the date hereof,  the
Highest Lawful Rate shall be automatically  increased or decreased,  as the case
may be,  from time to time as the  effective  date of each change in the Highest
Lawful Rate without  notice to Maker.  For purposes of  determining  the Highest
Lawful Rate under the Applicable Law of the State of Texas,  the applicable rate
ceiling  shall be the  indicated  rate  ceiling  described  in and  computed  in
accordance  with the  provisions of section  (a)(1) of Article  1.04;  provided,
however, that in determining the Highest Lawful Rate, all fees and other charges
contracted  for,  charged  or  received  by  Payee in  connection  with the loan
evidenced by this Note which are either deemed interest under  Applicable Law or
required under  Applicable Law to be deducted from the principal  balance hereof
to  determine  the rate of  interest  charged  by this Note  shall be taken into
account.  To the extent permitted by Applicable Law, Payee may from time to time
substitute for the "indicated rate ceiling"  referred to above any ceiling under
Article  1.04 or any other  statute  and  revise  the rate,  index,  formula  or
provision of law used to compute the rate hereunder as provided therein.


      (c) All  agreements  between  Maker and Payee,  whether  now  existing  or
hereafter  arising and whether written or oral, are hereby limited so that in no

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                   SECOND AMENDED AND RESTATED SENIOR SECURED
                             PROMISSORY NOTE, PAGE 2
<PAGE>

contingency,  whether by reason of demand or  acceleration of the Final Maturity
Date or otherwise, shall the interest contracted for, charged, received, paid or
agreed  to be  paid  to  Payee  exceed  the  maximum  amount  permissible  under
Applicable Law. If, from any circumstance  whatsoever,  interest would otherwise
be  payable  to Payee in  excess of the  maximum  amount  permissible  under the
Applicable  Law, the  interest  payable to Payee shall be reduced to the maximum
amount  permissible under the Applicable Law, and if from any circumstance Payee
shall ever receive  anything of value deemed  interest by the  Applicable Law in
excess of the maximum amount  permissible  under the  Applicable  Law, an amount
equal  to the  excessive  interest  shall be  applied  to the  reduction  of the
principal hereof and not to the payment of interest, or if such excessive amount
of interest exceeds the unpaid balance of principal hereof, such excess shall be
refunded to Maker. All interest paid or agreed to be paid to Payee shall, to the
extent  permitted by the Applicable Law, be amortized,  prorated,  allocated and
spread  throughout the full period  (including  any renewal or extension)  until
payment  in full of the  principal  so that the  interest  hereon  for such full
period shall not exceed the maximum amount permissible under the Applicable Law.
Payee expressly  disavows any intent to contract for, charge or receive interest
in an amount which exceeds the maximum amount  permissible  under the Applicable
Law. This paragraph shall control all agreements between Maker and Payee.

3. Pledge  Agreement.  Maker shall,  upon  execution of this Note and as partial
consideration for permitting the amendment, renewal, reinstatement,  replacement
and  extension of the  Telenational  Note,  as amended,  execute and cause to be
delivered to Bergman, Yonks, Stein & Bird, L.L.P., to the benefit of Payee, that
certain First Amended Pledge and Security  Agreement  (the APledge  Agreement@),
which Pledge Agreement  reinstates,  amends,  renews,  restates and replaces the
Telenational  Pledge  Agreement,  which Pledge  Agreement is attached  hereto as
Exhibit AA@, which by this reference is incorporated herein.

4. Payments.  All accrued unpaid interest through June 19, 1997 in the amount of
$15,880.79  together with unpaid principal in the sum of $262,278.06  (which sum
shall reduce the unpaid  principal  obligation of the Note from  $762,278.06  to
$500,000) shall be due and payable June 23, 1997.  Commencing  September 1, 1997
and on the first day of each of the four successive  calendar months thereafter,
Maker shall pay monthly the sum of $100,000  as  reduction  of  principal  owing
hereunder,  together with accrued  unpaid  interest due on such date of payment.
All accrued unpaid  interest,  together with all unpaid  principal and any other
sums due pursuant to the terms  hereof shall be due and payable  January 1, 1998
(the "Final Maturity Date").  In addition,  Maker shall, not later than June 23,
1997,  pay  attorney's  fees,  costs  and  expenses  incurred  by  Payee  in the
restructuring, enforcement and collection of the Telenational Note. All payments
to be made by Maker to the  Payee  hereunder  shall be made to the Payee at 2200
Ross Avenue,  Suite 4660 West,  Dallas,  Texas  75201,  not later than 4:00 p.m.
Central  Time on the date  when due in lawful  money of the  United  States  and
immediately available funds. The Maker will promptly and punctually pay when due
(whether on a scheduled  payment date or at maturity or upon the  prepayment  of
such Note) the  principal of and interest on the Note,  without any  presentment
thereof,  directly to the Holder of the Note at the address of such Holder shown
in the  register  maintained  by the Maker for such  purposes  or at such  other
address as the Holder  may from time to time  designate  in writing to the Maker

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                  SECOND AMENDED AND RESTATED SENIOR SECURED
                            PROMISSORY NOTE, PAGE 3
<PAGE>

or, if a bank  account is  designated  in any  written  notice to Maker from the
Holder,  the Maker will make such payments by wire transfer or other immediately
available funds to such bank account,  marked for attention as indicated,  or in
such  other  manner or to such  other  account  of the Holder in any bank in the
United States as such holder may from time to time direct in writing. The Holder
of the Note agrees that in the event it shall sell or transfer the Note it will,
prior to the delivery of the Note, make a notation thereon of all principal,  if
any,  prepaid on such Note and will also note thereon the date to which interest
has been paid on such Note.  Upon  repayment in full of the Note,  the Holder of
the Note shall deliver such Note to the Maker for cancellation.


5.    Affirmative  Covenants.  Each Maker covenants and agrees that so long as
the Note shall be outstanding:

      (a)   Principal  and  interest.  Maker  will  pay  or  cause  to  be  paid
            punctually  the  principal  of and interest on the Note at the times
            and places and in the manner specified in the Note.

      (b)   Maintenance of existence.  Maker will at all times do or cause to be
            done all  things  necessary  to  maintain,  preserve  and  renew its
            existence and its rights, patents and franchises.

      (c)   Maintenance  of  Properties,  Etc.  TCI shall  maintain its material
            properties  and assets in working  order and  condition and make all
            necessary repairs, renewals,  replacements,  additions,  betterments
            and  improvements  thereto,  so  that  the  business  carried  on in
            connection  therewith  may be  conducted  at all usual and  ordinary
            times.

      (d)   Compliance  with  laws.  Maker  will  comply  with all  applicable
            laws,  rules,  regulations,  and  orders of the  United  States of
            America  and  of  all  foreign  countries  and  of  any  state  or
            municipality,  and of any instrumentality or agency of any thereof
            (including   applicable   statutes,    regulations,   orders   and
            restrictions  relating  to  equal  employment   opportunities  and
            environmental  standards or controls) in respect of the conduct of
            business and the ownership of property by Maker.

      (e)   Insurance.  TCI will maintain  adequate  insurance with  financially
            sound and reputable insurance companies in such amounts and covering
            such risks as is customarily carried by companies engaged in similar
            businesses and similarly situated as TCI. TCI shall notify Holder of
            any  cancellations or material changes within five (5) business days
            of notice of such cancellation or change.

      (f)   Taxes,  assessments and other charges. Maker will pay punctually and
            discharge when due and payable: (i) all taxes, assessments and other
            governmental  charges  levied or imposed upon it or upon its income,
            profits  or  properties  and (ii)  all  claims  (including,  without
            limitation, claims for labor, materials, supplies or services) which
            might, if unpaid, become a lien upon any property of Maker.

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                  SECOND AMENDED AND RESTATED SENIOR SECURED
                            PROMISSORY NOTE, PAGE 4
<PAGE>

      (g)   Indebtedness.  Maker will pay  punctually and discharge when due and
            payable any indebtedness heretofore or hereafter incurred or assumed
            by it and discharge,  perform and observe the covenants,  provisions
            and conditions to be discharged,  performed and observed on the part
            of  Maker  in  connection  therewith,  or  in  connection  with  any
            agreement or other instrument relating thereto.

      (h)   Books.  Maker  will keep at all  times  proper  books of record  and
            account in which full,  true and correct entries will be made of its
            transactions  in  accordance  with  Generally  Accepted   Accounting
            Principles.

      (i)   Statements,  reports and  certificates to be delivered by WorldPort.
            From the date hereof and so long as the Holder  shall hold the Note,
            WorldPort  will  deliver  to  Holder  at the  address  shown  in the
            register maintained by WorldPort the following:

             (i)   Quarterly  financial  statements.  As  soon  as  reasonably
                   possible,  and in any event  within 45 days after the close
                   of each of the first three fiscal  quarters of WorldPort in
                   each fiscal year,  (1) the unaudited  consolidated  balance
                   sheet of  WorldPort  and TCI as of the end of such  period,
                   setting  forth  in  comparative   form  the   corresponding
                   figures  for the  preceding  fiscal  year end,  and (2) the
                   unaudited  consolidated  statements  of income and retained
                   earnings  and  cash  flows  of  WorldPort  and TCI for such
                   quarter  and for the  portion of the fiscal year ended with
                   such  quarter and  setting  forth in  comparative  form the
                   corresponding  figures for the corresponding periods of the
                   preceding  fiscal  year,  all  in  reasonable   detail  and
                   certified  by a principal  financial  officer of  WorldPort
                   subject to year-end audit adjustments.

             (ii)  Other  reports and  statements.  Promptly  upon the mailing
                   to its  equity  holders  of each  annual  report  or  other
                   report  or  communication,  a copy of each  such  report or
                   communication;  and  promptly  upon any filing by WorldPort
                   with  the  Securities  and  Exchange  Commission,   or  any
                   governmental agency or agencies  substituted  therefor,  or
                   with any  national  securities  exchange,  of any annual of
                   periodic or special  report or  registration  statement,  a
                   copy of such report or statement.

      (j)   Certificate  of  Default.   Maker  will  deliver  to  the  Holder,
            forthwith  upon  becoming  aware of any default or defaults in the
            performance of any covenant,  agreement or condition  contained in
            the Note and any related document,  including the Pledge Agreement
            (including  notice of any event  which  with the giving of notice,
            lapse  of time or both  would  become  an Event  of  Default),  an
            Officer=s=   Certificate  specifying  such  default  or  event  of
            default.

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                  SECOND AMENDED AND RESTATED SENIOR SECURED
                            PROMISSORY NOTE, PAGE 5
<PAGE>

      (k)   Additional information. Maker will deliver to Holder such other data
            and information as from time to time may be reasonably  requested by
            the Holder.

      (l)   Other  Documents.  Maker  will  comply  with all  other  convenants,
            representations,  warranties,  terms and obligations of any document
            related  hereto,  including  that certain Loan  Agreement and Pledge
            Agreement.

6.    Negative  Covenants.  Each Maker  covenants  and agrees  that so long as
the Note shall be outstanding:

      (a)    Guarantees.  TCI will not guarantee,  directly or  indirectly,  any
             obligation  or  indebtedness  of any other Person.  "Person"  shall
             include any individual,  a corporation,  a partnership,  a business
             entity,  or a  government,  foreign or  domestic,  or any agency or
             political subdivision thereof.

      (b)    Disposition of assets. TCI will not sell, assign,  lease,  transfer
             or  otherwise  dispose of all or any portion of its  properties  or
             assets  to  any  third  party,  in any  transaction  or  series  of
             transactions.

      (c)    Senior Debt.  Subsequent to the date hereof,  Maker will not incur,
             create,  assume  or at any  time  become  liable,  contingently  or
             otherwise for any borrowed or other  indebtedness that is senior in
             right of payment to the obligations created herein.  Nothing herein
             shall be construed to permit the issuance of any indebtedness  that
             would be secured by any  Collateral  granted to the Payee to secure
             the terms herein.

7.  Negotiability;  Offsets,  Defenses  or  Counterclaims.  This  Note is freely
negotiable. The respective Maker knows of no defenses, setoffs, or counterclaims
existing  as of the date  hereof  which  could be  asserted  or  brought  by the
respective  Maker or any other party in any suit or action for the collection of
any sum due hereunder.

8.    Event of  Default.  An Event of  Default  shall mean the  occurrence  or
existence of any one or more of the following events,  whether such occurrence
is voluntary or  involuntary or comes about or is effected by operation of law
or  pursuant to or in  compliance  with any  judgment,  decree or order of any
court or any order,  rule or regulation of any  administrative or governmental
authority: If either Maker

      a.     should fail to pay the  principal  of, or interest  on, this Note
             as and when due and payable,  which failure shall  continue for a
             period of twenty (20) days;

      b.     shall fail to perform or observe any term,  covenant,  or agreement
             contained herein, in the Loan Agreement, in the Pledge Agreement or
             any document  related  hereto,  which failure shall  continue for a
             period of twenty (20) days after  Payee gives Maker  notice of such
             failure;

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                  SECOND AMENDED AND RESTATED SENIOR SECURED
                            PROMISSORY NOTE, PAGE 6
<PAGE>

      c.    If any  representation,  warranty or other statement of fact herein,
            in the Loan Agreement or in the Pledge Agreement, or in any writing,
            certificate,  report or  statement  at any time  furnished  to Payee
            pursuant to or in connection  herewith  shall be false or misleading
            in any material respect; or

      d.    admit in  writing  either  of their  respective  inability  to pay
            debts  generally  as they become due;  files a petition for relief
            under the  bankruptcy  laws or a petition to take advantage of any
            insolvency  act; makes an assignment for the benefit of creditors;
            commences  a  proceeding  for  the   appointment  of  a  receiver,
            trustee,  liquidator or  conservator of itself or the whole or any
            substantial  part of its  property;  files a  petition  or  answer
            seeking  reorganization or arrangement or similar relief under the
            Federal  Bankruptcy Laws or any other applicable law or statute of
            the  United  States  or any  State;  is  adjudged  a  bankrupt  or
            insolvent,  or a court of competent  jurisdiction  shall enter any
            order,   judgment  or  decree  appointing  a  receiver,   trustee,
            liquidator or  conservator  of either Maker or of the whole or any
            substantial  part of the  property  of either  Maker or approves a
            petition  filed  against  either Maker seeking  reorganization  or
            similar  relief  under the  Federal  Bankruptcy  Laws or any other
            applicable  law or statute of the United  States or any State;  or
            if,  under the  provisions  of any other law for the relief or aid
            of either Maker,  a court of competent  jurisdiction  shall assume
            custody  or   control  of  either   Maker  or  the  whole  or  any
            substantial  part  of  its  property;  or if  there  is  commenced
            against  either  Maker  any  proceeding  for any of the  foregoing
            relief;  or if either  Maker,  by any act indicates its consent to
            approval of, or acquiescence in any such proceeding;  either Maker
            generally,  does not pay,  or shall  be  unable  to pay,  or shall
            admit in  writing  its  inability  to pay its debts as such  debts
            become due; or

      e.    If any creditor of either Maker for any reason whatsoever  hereafter
            shall  accelerate  payment  in whole  or in part of any  outstanding
            material  obligation  owed to it by either Maker under any agreement
            or  arrangement,  or if any  judgment  against  either  Maker or any
            execution against any of its property of either Maker for any amount
            remains  unpaid,  unstayed or undismissed  for a period in excess of
            ten days; or

      f     If either Maker shall cease to exist.


      It is understood and agreed that time is of the essence in the performance
of the  Note.  If an  Event  of  Default  exists,  then  the  Note  at the  time
outstanding  shall  immediately  become due and payable  together  with interest
accrued  thereon  without  presentment,  demand,  protest or notice of any kind,
including  notice of intent to accelerate  the payment of the unpaid  balance of
the Note or of notice of  acceleration,  all of which are  hereby  waived by the
Maker. The Holder of the Note may also proceed to protect and enforce its rights
against  either or both Maker either by suit in equity  and/or by action at law,
or by other appropriate  proceedings,  whether for the specific  performance (to

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                  SECOND AMENDED AND RESTATED SENIOR SECURED
                            PROMISSORY NOTE, PAGE 7
<PAGE>
the extent  permitted  by law) of any  covenant or  agreement  contained in such
Note,  or in aid of the  exercise  of any power  granted  in such  Note,  or may
proceed to enforce  the  payment of such Note or to enforce  any other  legal or
equitable right of the holder of such Note.

9. Notices. Any request,  demand,  authorization,  direction,  notice,  consent,
waiver,  or other  document  provided or permitted by this Note to be made upon,
given or  furnished  to, or filed with the Maker shall be  sufficient  for every
purpose  hereunder  if in writing  and mailed,  registered  or  certified  mail,
postage prepaid, or delivered by facsimile or telecopy to each Maker,  addressed
to each Maker at 9601 Katy Freeway, Suite 200, Houston, Texas 77024,  telecopier
number (713)  461-8098,  (or such other address,  or telecopier  number,  as the
respective  Maker may from time to time  direct).  Any notice to Payee  shall be
sufficiently  given if in writing  and mailed,  registered  or  certified  mail,
postage prepaid, to the address set forth herein (or such other address as Payee
may from time to time  direct).  Any notice to a Holder (other than Payee) shall
be  sufficiently  given if in writing and mailed,  registered or certified mail,
postage prepaid, to such address as Holder shall from time to time direct.

10.  Consents,  Waivers  and  Modifications.  No term,  covenant,  agreement  or
condition of the Note may be amended,  supplemented  or modified,  or compliance
therewith  waived  (either  generally  or in a  particular  instance  and either
retroactively or prospectively),  except pursuant to a written instrument signed
by the Maker and the  Holder.  No course of  dealing  between  the Maker and the
Holder of the Note or any delay or failure on the part of the Holder of the Note
in exercising  any rights  hereunder  shall operate as a waiver of any rights of
such holder.

11. Governing Law. THIS NOTE SHALL BE INTERPRETED AND THE RIGHTS AND LIABILITIES
OF THE PARTIES  HERETO  DETERMINED  IN  ACCORDANCE  WITH THE  INTERNAL  LAWS (AS
OPPOSED TO CONFLICTS  OF LAW  PROVISIONS)  AND  DECISIONS OF THE STATE OF TEXAS.
WHENEVER  POSSIBLE  EACH  PROVISION  OF THIS NOTE SHALL BE  INTERPRETED  IN SUCH
MANNER AS TO BE EFFECTIVE AND VALID UNDER  APPLICABLE  LAW, BUT IF ANY PROVISION
OF THIS NOTE  SHALL BE  PROHIBITED  BY OR INVALID  UNDER  APPLICABLE  LAW,  SUCH
PROVISION SHALL BE INEFFECTIVE TO THE EXTENT OF SUCH  PROHIBITION OR INVALIDITY,
WITHOUT INVALIDATING THE REMAINDER OF SUCH PROVISION OR THE REMAINING PROVISIONS
OF THIS NOTE. WHENEVER IN THIS NOTE REFERENCE IS MADE TO THE PAYEE OR THE MAKER,
SUCH REFERENCE SHALL BE DEEMED TO INCLUDE,  AS APPLICABLE,  A REFERENCE TO THEIR
RESPECTIVE  SUCCESSORS AND ASSIGNS. THE PROVISIONS OF THIS NOTE SHALL BE BINDING
UPON AND SHALL INURE TO THE BENEFIT OF SUCH  SUCCESSOR AND ASSIGNS.  THE MAKER'S
SUCCESSORS AND ASSIGNS SHALL INCLUDE, WITHOUT LIMITATION, A RECEIVER, TRUSTEE OR
DEBTOR IN POSSESSION FOR THE MAKER.

12.  Securities Laws. THIS NOTE HAS NOT BEEN REGISTERED UNDER THE SECURITIES ACT
OF 1933,  AS  AMENDED,  OR UNDER THE  SECURITIES  LAWS OF ANY  STATE.  THIS NOTE
THEREFORE  MAY  NOT  BE  SOLD,  TRANSFERRED,  ASSIGNED,  PLEDGED,  OR  OTHERWISE
DISTRIBUTED  FOR VALUE IN THE  ABSENCE OF (i) AN  OPINION OF COUNSEL  REASONABLY

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                  SECOND AMENDED AND RESTATED SENIOR SECURED
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<PAGE>
ACCEPTABLE TO THE MAKER THAT SUCH SALE,  TRANSFER,  ASSIGNMENT,  PLEDGE OR OTHER
DISTRIBUTION IS EXEMPT FROM (OR NOT OTHERWISE  SUBJECT TO) THE  REGISTRATION (OR
QUALIFICATION) AND PROSPECTUS DELIVERY REQUIREMENTS OF SUCH ACT OR LAWS, OR (ii)
SUCH REGISTRATION OR QUALIFICATION.

13. Attorneys Fees. In the case of a default, the Maker shall pay to the Holder,
to the extent  permitted by law,  such further  amount as shall be sufficient to
cover  the  cost and  expense  of  collection,  including  (without  limitation)
reasonable attorneys' fees, costs and expenses.

14. Waiver of Protest.  The Maker  expressly  waives  demand,  grace,  notice of
intent to  accelerate,  notice of  acceleration,  presentment  for payment,  and
protest,  and  further  agrees  that this Note and the Pledge  Agreement  may be
renewed, and the time for payment extended without notice.

15.   Successors and Assigns.  All the covenants,  stipulations,  promises and
agreements in this Note  contained by or on behalf of the Maker shall bind its
successors and assigns, whether so expressed or not.

16.   Headings.  The  headings of the  Sections of this Note are  inserted for
convenience only and shall not be deemed to constitute a part of this Note.

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<PAGE>


      IN WITNESS WHEREOF, the Maker has caused this Note to be duly executed and
delivered as of the date first above written.

                               WORLDPORT COMMUNICATIONS, INC.


                               By:  /s/John Dalton
                                    ---------------------------------

                               Its: President & C.E.O.
                                    ---------------------------------


                               TELENATIONAL COMMUNICATIONS, INC.

                               By:  /s/John Dalton
                                    ---------------------------------

                               Its: President & C.E.O.
                                    ---------------------------------












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