FIRST AMENDED
                          PLEDGE AND SECURITY AGREEMENT


                                                                   June 20, 1997
                                                                 Omaha, Nebraska

      This FIRST AMENDED PLEDGE AND SECURITY AGREEMENT (this "Agreement"), dated
as of June 20, 1997, is entered into by and between Telenational Communications,
Inc., a Delaware  Corporation ("the Pledgor") and Value Partners,  Ltd., a Texas
limited partnership (the "Secured Party"), in order to secure the payment of the
indebtedness hereinafter referred to of Pledgor
to the Secured Party.

                                 R E C I T A L S

1.  On  or  about  November  8,  1995,   Telenational   Communications   Limited
Partnership,  a Nebraska limited partnership  ("Telenational") executed as maker
that certain  Unsecured  Senior  Promissory  Note (the  "Original  Note") in the
principal sum of Eight Hundred Fifty Thousand and no/l00  Dollars  ($850,000.00)
to Aden  Enterprises,  Inc., d/b/a ECDI,  Inc., as Payee ("Aden").  The Original
Note was pledged  and  assigned  by Aden to the  Secured  Party and  acquired at
public sale by the Secured Party  pursuant to that certain  Amended and Restated
Pledge Agreement  executed by Aden in favor of the Secured Party and dated as of
December 8, 1995.

2.  Telenational  defaulted  on the  Original  Note.  As a  condition  to and in
consideration  of the Secured  Party  reinstating,  renewing,  and extending the
Original Note to Telenational in the amount of $850,000.00,  Telenational agreed
(i) to enter into and execute that certain Amended and Restated  Promissory Note
dated  March  20,  1997  (the  "Telenational  Note"),  and (ii) to pledge to the
Secured Party (a) all of the personal  property of Telenational,  including that
set forth in Exhibit "A" attached hereto and made a part hereof,  (the "Personal
Property") and (b) 850,000 shares of Series A  noncumulative  Preferred Stock of
Enhanced Telecommunications Services, Inc., owned by Telenational, (the "Pledged
Securities")  pursuant to that certain Pledge and Security Agreement dated March
20, 1997 (the  "Telenational  Pledge  Agreement").  The Telenational  Note, that
certain Loan Modification  Agreement dated March 20, 1997 by and between Secured
Party and  Telenational,  the  Telenational  Pledge  Agreement and all financing
statements   and  related   documents   shall  be  referred  to  herein  as  the
"Telenational Documents".

3. Pledgor desires to acquire the Personal Property from  Telenational,  subject
to the security  interest granted the Secured Party in the  Telenational  Pledge
Agreement. WorldPort Communications, Inc. ("WorldPort") and Telenational entered
into that  certain  Asset  Purchase  Agreement  dated April 23, 1997 (the "Asset
Purchase  Agreement"),  pursuant to which TCI, as assignee of  WorldPort,  is to
acquire  the  Personal  Property,  subject to the  security  interest of Secured
Party,  as  modified  in the Loan  Documents  (as that term is defined  herein).
Pledgor and its parent, WorldPort, have executed that certain Second Amended and

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Restated  Senior  Secured  Promissory  Note (the "Note") and that certain  First
Amended Loan  Modification  Agreement (the "Loan Agreement") and the Pledgor has
executed this  Agreement.  The Note, this  Agreement,  the Loan Agreement,  that
certain  Certificate of No Oral Agreements,  financing  statements as amended by
the Pledgor (the  "Financing  Statements")  and all related  documents  shall be
referred to herein as the "Loan Documents". This Agreement is entitled to all of
the liens, benefits,  priorities, rights and privileges, as amended, reinstated,
restated, replaced, modified and granted herein and in the other Loan Documents,
which are hereby ratified and carried  forward in full force and effect,  of the
Original Note and the Telenational Documents.

                                A G R E E M E N T

      NOW,  THEREFORE,  in consideration of the foregoing and for other good and
valuable  consideration,  the  receipt  and  sufficiency  of  which  are  hereby
acknowledged, the parties hereto agree as follows:

      Section 1.  Definitions.  Capitalized  terms used herein  shall have the
meaning specified herein.

      Section 2.  Pledge.

      (a) Pledgor Pledgor hereby pledges,  assigns,  transfers,  and delivers to
          the Secured Party, and hereby grants a security interest,  and renews,
          assumes and affirms the existing security interest of Secured Party in
          the following (the "Collateral"):  (a) the Personal Property,  and (b)
          all of the  property  compromising  the  Personal  Property  , and all
          proceeds  thereof and all  substitutions,  replacements and accessions
          thereto. Cash proceeds from the Collateral shall promptly be delivered
          to the Secured Party and shall, at the option of the Secured Party, be
          held as Collateral  for the Note and/or be applied to the  obligations
          of the Pledgor and WorldPort arising under the Loan Documents.


      (b) The  pledge of the  Collateral  shall be  referred  to herein as the
          "Security Interest".

      (c) Pledgor assumes all obligations of Telenational under the Telenational
          Pledge Agreement,  as modified herein. This Agreement amends,  renews,
          restates,  reinstates  replaces  and  affirms  the  security  interest
          granted  Pledgor in the  Telenational  Pledge  Agreement,  as modified
          herein,  and the Pledgor  expressly affirms that such priority created
          therein is affirmed herein.


      Section 3. Secured Obligations.  The Security Interest shall secure, under
the circumstances  set forth herein,  the Secured  Obligations.  For purposes of
this Agreement,  the term "Secured Obligations" shall mean the following (i) the
due and punctual payment and performance of the Note, and (ii) the reimbursement
of all costs incurred by the Secured Party to maintain, preserve and enforce the
Note, the Loan Agreement and this Agreement, collect the Secured Obligations and
maintain and preserve the Collateral,  including without  limitation the Secured

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Party's reasonable  attorneys' fees,  disbursements and legal expenses,  and all
expenditures  by  Secured  Party  for  taxes,   insurance  and  repairs  to  and
maintenance of the Collateral.

      Section 4. Pledgor's Obligations to Pay. Pledgor shall pay and perform all
of the Secured  Obligations  and any and all  obligations  set forth in the Loan
Documents as the same may become due according to their terms.  Pledgor shall be
liable for,  and shall  reimburse  to Secured  Party,  all  expenses,  including
reasonable  attorneys= fees,  incurred or paid in connection with  establishing,
perfecting,  maintaining,  protecting or enforcing any of Secured Party=s rights
and remedies hereunder,  including in, retaking,  holding, preparing for sale or
lease, or selling and leasing, and the like, the Collateral.

      Section 5. Protection of the Collateral. Pledgor shall defend the title to
the  Collateral  against  all claims and  demands  whatsoever.  Other than those
encumbrances  set forth in Exhibit "B",  attached  hereto and by this  reference
incorporated herein, Pledgor shall keep the respective Collateral free and clear
of all liens, charges,  encumbrances,  taxes and assessments,  and shall pay all
taxes, assessments and fees relating to the Collateral.  Upon request by Secured
Party,  Pledgor,  at the Pledgor's expense,  shall furnish further assurances of
title,  execute any further  instruments  and documents,  and do any other acts,
that  Secured  Party may  request,  necessary  to  effectuate  the  purposes and
provisions  of this  Agreement,  including,  in order to perfect and protect the
Security  Interest  granted or purported  to be granted  hereby or to enable the
Secured  Party to exercise  and enforce the rights and remedies  hereunder  with
respect to any Collateral.

      Pledgor shall not further sell,  exchange,  assign,  transfer or otherwise
dispose  of  the  Collateral,  and  shall  not  further  encumber,  hypothecate,
mortgage,  create a lien on or security interest in the Collateral,  without the
prior written consent of Secured Party in each instance. The risk of loss of the
Collateral  at all times shall be borne by the Pledgor.  Pledgor  shall keep the
Collateral in good repair and condition and shall not misuse, abuse or waste the
Collateral  or allow the  Collateral to  deteriorate  except for normal wear and
tear.

      Pledgor at all times shall maintain: (a) insurance covering the Collateral
and all  other  property  of  Pledgor  against  loss or damage by fire and other
hazards;  (b)  insurance  against  liability on account of damage to persons and
property;  (c) all insurance  required under applicable  workmen=s  compensation
laws;  and (d) insurance  covering such other risks as Secured Party  reasonably
may request.  Such insurance shall be in amounts  satisfactory to Secured Party,
shall be maintained with responsible insurance carriers,  shall name Pledgor and
Secured Party as their interests may appear as insured, and shall provide for at
least thirty (30) days notice to Secured  Party prior to  cancellation.  Pledgor
from time to time, shall upon Secured Party=s written request,  promptly furnish
or cause to be furnished to Secured  Party  evidence of the  maintenance  of all
insurance  required to be  maintained  hereunder,  including  such  originals or
copies of policies,  certificates of insurance, riders and endorsements relating
thereto  and proof of  payment of  premiums  as Secured  Party may  request.  If
Pledgor shall fail to maintain any such insurance,  Secured Party may, but shall
not be obligated  to, do so at the expense of Pledgor,  in addition to the other
rights and remedies of Secured Party.  Pledgor hereby appoints Secured Party the
attorney in fact of Pledgor for purposes of  obtaining,  adjusting and canceling
any such  insurance  and  endorsing  settlement  drafts,  and hereby  assigns to

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Secured Party all sums which may become payable under such insurance,  including
returned  premiums  and  dividends,  as  additional  security  for  the  Secured
Obligations.

      The  Collateral  shall  be kept at  Pledgor's  place of  business  at 7300
Woolworth  Ave.,  Omaha,   Nebraska  68124,  except  for  temporary  removal  in
connection with its ordinary use or unless Pledgor shall have obtained the prior
written  consent of Secured Party for its removal to another  location.  Secured
Party shall have the right to enter upon  Pledgor's  premises at any  reasonable
time, and from time to time, to inspect the Collateral.


      Section 6.  Filing and  Recording.  Pledgor  shall  execute and deliver to
Secured Party any financing statements,  and shall procure for Secured Party any
other  documents,  necessary or  appropriate  to protect the  security  interest
granted,  renewed,  amended,  reinstated,  assumed and extended to Secured Party
hereunder  and in the  Telenational  Pledge  Agreement  against  the  rights and
interests of third parties,  and shall cooperate with the Secured Party to cause
the same to be duly  filed in all  places  necessary  to  perfect  the  security
interest of Secured Party in the Collateral.  In the event that any recording or
refiling  thereof (or filing of any statements of  continuation or assignment of
any  financing  statement)  is required to protect and  preserve  such  security
interest,  Pledgor,  at its own cost and  expense,  shall  cause  the same to be
re-recorded  and/or  refiled at the time and in the manner  requested by Secured
Party.  Pledgor hereby authorizes  Secured Party to file or refile any financing
statements,  continuation statements,  and/or amended statements with respect to
the security interest granted pursuant to this Agreement which at anytime may be
required  or  appropriate,  although  the same may have  been  executed  only by
Secured  Party,  and to execute such  financing  statement on behalf of Pledgor.
Pledgor hereby irrevocably designates Secured Party, its agents, representatives
and  designees,  as agent and  attorney-in-fact  for Pledgor  for the  aforesaid
purposes.

      Section 7.  Representations and Warranties.


      Pledgor represents and warrants to the Secured Party as follows:

            (i) Pledgor is not in default under any indenture, mortgage, deed of
      trust, agreement or other instrument to which it is a party or by which it
      may be bound.  Neither the execution  nor the delivery of this  Agreement,
      nor  the  consummation  of  the  transactions  herein  contemplated,   nor
      compliance with the provisions hereof, will violate any law or regulation,
      or any order or decree of any  court or  governmental  authority,  or will
      conflict  with, or result in the breach of, or constitute a default under,
      any indenture,  mortgage,  deed or trust, agreement or other instrument to
      which  Pledgor is a party or by which  Pledgor may be bound,  or result in
      the creation or  imposition  of any lien,  claim or  encumbrance  upon any
      property of Pledgor.

            (ii)  Pledgor  has  the  power to  execute,  deliver and perform the
      provisions  of  this agreement and all instruments and documents delivered

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      or to be delivered  pursuant  hereto,  and has taken or caused to be taken
      all necessary or appropriate  actions to authorize the execution, delivery
      and performance of this Agreement and all such instruments and documents.

            (iii) The  property  described on Exhibit "A" hereto is all personal
      property of any kind or nature owned,  either  directly or indirectly,  by
      Pledgor as of closing of the Asset Purchase Agreement.

            (iv)  Pledgor is the legal and  equitable  owner of the  Collateral,
      subject to the interest  therein granted  Secured Party.  The ownership by
      Pledgor of the  Collateral  is free and clear of all  security  interests,
      liens,  claims and  encumbrances  of every kind and nature,  except as set
      forth in Exhibit  "B"  hereto.  Except as may be set forth in Exhibit  "B"
      annexed  hereto,  no financing  statement  covering the  Collateral or its
      proceeds  is on  file  in any  public  office.  Nothing  herein  shall  be
      construed  either as a consent by Secured  Party to the  validity  of such
      encumbrances  or as a waiver of  Secured  Party's  right to  contest  such
      encumbrances.

            (v) No  default  exists,  and no event  which  with  notice  or  the
      passage of time or both,  would  constitute a default under the Collateral
      by any part thereto, and there are no offsets, claims or defenses  against
      the  obligations evidenced by the Collateral, except  as may be  expressly
      set forth in Exhibit "B" annexed hereto.

            (vi)  The  Security   Interest   constitutes  a  valid  and,  upon
      delivery of documents necessary  to perfect the Secured  Party=s  security
      interest  in  the  Collateral,  a  perfected  security   interest  in  the
      Collateral for payment and performance of the Secured Obligations, subject
      only to those liens and encumbrances of record as set forth in Exhibit "B"
      attached hereto and by this reference incorporated herein.

      All  representations  and  warranties  of Pledgor  contained  herein shall
survive  the  execution,  delivery  and  performance  of  this  Agreement  until
termination of this Agreement under Section 20.

      Section 8. Release of Collateral.  The Pledgor shall not sell or otherwise
dispose of the Collateral,  or any part thereof or any interest therein.  If the
Collateral,  or any part thereof,  is sold or otherwise disposed of in violation
of these  provisions,  the Security Interest of the Secured Party shall continue
in such  Collateral  or any  part  thereof  notwithstanding  such  sale or other
disposition,  and Pledgor will deliver any proceeds thereof to the Secured Party
to be, at the option of the Secured Party, held as Collateral hereunder,  and/or
be applied to the obligations of the Pledgor.

      Section  9.  Secured  Party  Appointed  Attorney-in-Fact.  Pledgor  hereby
irrevocably appoints the Secured Party as Pledgor's attorney-in-fact,  with full
authority  in the place and stead of any Pledgor  and in its name or  otherwise,
from time to time in the Secured Party's  discretion,  to take any action and to
execute any instrument that the Secured Party may deem  reasonably  necessary or
advisable to  accomplish  the  purposes of this  Agreement,  including,  without
limitation,  to receive,  endorse and collect all  instruments  made  payable to
Pledgor  representing any dividend,  interest  payment or other  distribution in
respect of the Collateral or any part thereof and to give full discharge for the
same, when and to the extent permitted by this Agreement.

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      Section 10. Secured Party May Perform.  Upon the occurrence and during the
continuance of an Event of Default (including an Event of Default resulting from
a failure to perform any agreement  contained  herein),  if the Pledgor fails to
perform any agreement contained herein, the Secured Party may itself perform, or
cause  performance  of, such  agreement,  and the expenses of the Secured  Party
incurred in connection therewith shall be payable by Pledgor under Section 15.

      Section 11. Reasonable Care. The Secured Party shall have an obligation to
exercise reasonable care with respect to Collateral in its possession; provided,
however,  that the Secured  Party shall be deemed to have  exercised  reasonable
care if the Collateral is accorded  treatment  substantially  comparable to that
which the Secured Party accords its own property or treatment  substantially  in
accordance  with actions  requested by Pledgor in writing  (although the Secured
Party shall not be obligated to comply with any such  requests and no failure to
do so shall be deemed to be a failure to exercise reasonable care).

      Section 12.  Events of Default

      The  occurrence  of any one or more of the following  events  (hereinafter
referred  to as AEvents  of  Default@)  shall  constitute  a default  hereunder,
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:

            (a) If a default in the payment of any  principal  or interest due
            under the Note shall occur; or

            (b) If a failure to pay, perform or observe any covenant, agreement,
            term or provision of the Loan  Documents,  or any other agreement or
            arrangement now or hereafter entered into between the parties to the
            Loan Documents shall occur; or

            (c) If any Event of Default  shall occur under the terms of the Note
            or the Loan Agreement.

            (d)  If  there  shall  occur  any  reduction  in  the  value  of the
            Collateral  or any  act of any of the  Pledgor  which  imperils  the
            prospect  of the full  performance  or  satisfaction  of the Secured
            Obligations; or

            (e)  If all  of or  any  part  of  the  Collateral  shall  be  sold,
            transferred   or   assigned,   or  shall  be   further   encumbered,
            hypothecated,  mortgaged,  or  made  subject  to any  other  lien or
            security  interest,  without  the prior  written  consent of Secured
            Party.

      Section 14.  Remedies

      If upon or after the occurrence of any Event of Default, the Secured Party
elects to exercise  remedies under this  Agreement  (the  occurrence of any such

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event shall be  referred  to as an  "Acceleration"),  then upon  minimum  notice
required by applicable law the Secured  Obligations shall immediately become due
and payable in full without notice or demand and the following  provisions shall
apply:

            (a) The  Secured  Party  may,  with or  without  notice to  Pledgor,
            foreclose  the security  interest  created  herein by any  available
            judicial  procedure,  or take possession of the  Collateral,  or any
            portion  thereof,  with or without judicial  process,  and enter any
            premises  where the  Collateral  may be located  for the  purpose of
            taking  possession  of or removing the same,  or rendering  the same
            unusable,  or  disposing of the  Collateral  on such  premises,  and
            Pledgor agrees not to resist or interfere therewith;

            (b) The Secured  Party may require  Pledgor to prepare,  assemble or
            collect the Collateral,  at Pledgor's own expense, and make the same
            available  to  Secured  Party at such  place as  Secured  Party  may
            designate, whether at Pledgor's premises or elsewhere;

            (c)  The  Secured  Party  may  exercise  (in  compliance   with  all
            applicable  securities  laws)  in  respect  of  the  Collateral,  in
            addition  to other  rights  and  remedies  provided  for  herein  or
            otherwise  available to it, all the rights and remedies of a secured
            party after default under the Uniform  Commercial  Code in effect in
            the State of Texas at that  time,  and the  Secured  Party may also,
            without  notice  except as  specified  below,  sell with or  without
            representations or warranties, the Collateral or any part thereof in
            one or more parcels at public or private sale, at any exchange, over
            the  counter or at the Secured  Party's  offices or  elsewhere,  for
            cash, on credit or for future delivery,  and at such price or prices
            and upon  such  other  terms as the  Secured  Party  may in its sole
            discretion deem commercially  reasonable or otherwise in such manner
            as necessary to comply with applicable  federal and state securities
            laws.  Upon  consummation  of any such sale, the Secured Party shall
            have the right to assign,  transfer and deliver to the  purchaser or
            purchasers  at any  such  sale and such  purchasers  shall  hold the
            property sold  absolutely,  free from any claim or right on the part
            of any Pledgor,  and Pledgor hereby waives (to the extent  permitted
            by Law) all rights of redemption,  stay or appraisal that it now has
            or may at any  time in the  future  have  under  any  rule of law or
            statute now existing or hereafter enacted;

            (d) The Secured  Party may execute and deliver  documents  of title,
            certificates  of origin,  or other evidence of payment,  shipment or
            storage of any  Collateral  or proceeds on behalf of and in the name
            of Pledgor;

            (e)  Should  Pledgor  fail to cure  any  default  within  three  (3)
            business days of receiving  written  notice of such default from the
            Secured  Party the  Secured  Party may remedy any default by Pledgor
            hereunder,  without waiving such default, and any monies expended in
            so doing shall be  chargeable  with interest to Pledgor and added to
            the Secured Obligations secured hereby;

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            (f) The Secured Party may apply for a temporary  restraining  order,
            and/or an injunction  to restrain a breach or  threatened  breach of
            this Agreement by Pledgor;

            (g) Pledgor  agrees that the Secured  Party shall not be required to
            register or qualify any of the Collateral  under applicable state or
            federal securities laws in connection with any such sale if the sale
            is effected in a manner that  complies with all  applicable  federal
            and state securities laws or exemptions therefrom. The Secured Party
            shall be authorized at any such sale (if it deems it advisable to do
            so) to restrict the prospective bidders or purchasers to persons who
            will represent and agree that they are purchasing the Collateral for
            their  own  account  for  investment  and  not  with a  view  to the
            distribution or sale thereof.  In the event that any such Collateral
            is sold at private sale,  Pledgor agrees that if such  Collateral is
            sold for a price that the Secured Party in good faith believes to be
            reasonable under the circumstances then existing,  then (a) the sale
            shall be deemed to be commercially  reasonable in all respects,  (b)
            Pledgor  shall  not be  entitled  to a credit  against  the  Secured
            Obligations  in an amount in excess of the purchase  price,  and (c)
            the Secured Party shall not incur any liability or responsibility to
            Pledgor in connection  therewith,  notwithstanding  the  possibility
            that a  substantially  higher  price  might have been  realized at a
            public sale.  Pledgor  hereby waives any claims  against the Secured
            Party  arising  by  reason  of the fact  that the price at which the
            Collateral may have been sold at such private sale was less than the
            price  which  might have been  obtained at a public sale or was less
            than the Secured Obligations,  even if the Secured Party accepts the
            first offer  received and does not offer the Collateral to more than
            one offeree  (other than the Secured  Party or an  affiliate  of the
            Secured  Party),  unless such sale was not  commercially  reasonable
            under the circumstances;

            (h) To the  extent  notice of sale  shall be  required  by law,  the
            Secured  Party  shall  give the  Pledgor at least ten (10) days' (or
            such longer period as shall be specified by applicable  laws) notice
            of the time and place of any public sale or the time after which any
            private sale is to be made,  which Pledgor  agrees shall  constitute
            commercially reasonable notification.  At any such sale, the Secured
            Party, to the extent permitted by law, may bid (which bid may be, in
            whole  or  in  part,  in  the  form  of   cancellation   of  Secured
            Obligations)  for and purchase for the account of the Secured  Party
            the whole or any part of the Collateral. The Secured Party shall not
            be obligated to make any sale of Collateral  regardless of notice of
            sale having been given.  The Secured Party may adjourn any public or
            private sale from time to time by announcement at the time and place
            fixed therefor,  and such sale may, without further notice,  be made
            at the time and place to which it was so  adjourned.  If sale of all
            or any  part  of the  Collateral  is made on  credit  or for  future
            delivery,  the  Collateral  so sold may be  retained  by the Secured
            Party until the sale price is paid by the  purchaser  or  purchasers
            thereof, but the Secured Party shall not incur any liability in case
            any such  purchaser or purchasers  shall fail to take up and pay for
            the  Collateral  so sold  and,  in case of any  such  failure,  such
            Collateral  may be sold again upon like notice.  Pledgor agrees that
            any  sale  of the  Collateral  conducted  by the  Secured  Party  in
            accordance with the foregoing provisions of this Section 14(h) shall
            be deemed to be a  commercially  reasonable  sale under the  Uniform

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            Commercial  Code as in  effect  in the  State of Texas  from time to
            time;

            (i) As an  alternative  to  exercising  the  power  of  sale  herein
            conferred  upon it, the Secured Party may proceed by a suit or suits
            at law or in equity to foreclose the security interest granted under
            this Agreement and to sell the Collateral,  or any portion  thereof,
            pursuant to a judgment  or decree of a court or courts of  competent
            jurisdiction;

            (j) Any cash held by the Secured  Party as  Collateral  and all cash
            proceeds  received by the  Secured  Party in respect of any sale of,
            collection  from, or other  realization  upon all or any part of the
            Collateral (i) prior to the occurrence of an Acceleration  shall, at
            the  option of the  Secured  Party,  be  applied  as is set forth in
            subparts  (x) and (y) of this  paragraph,  or be held by the Secured
            Party as collateral  for the Note, and (ii) following the occurrence
            of an  Acceleration  may be held by the Secured  Party as Collateral
            and/or then or at any time thereafter applied as follows: (x) first,
            to the  payment to the  Secured  Party of the costs and  expenses of
            retaking,  holding and preparing for sale of the  Collateral and any
            other fees, expenses,  claims, demands, losses,  judgments,  damages
            and liabilities arising out of or related to any Loan Document which
            are payable to the Secured Party,  including arising in the Note and
            this Agreement, and (y) second, to the Secured Party for application
            against or on account of all or any part of the Note; and

            (k) Any  surplus of such cash or cash  proceeds  held by the Secured
            Party and  remaining  after payment in full of all the Note shall be
            reassigned and redelivered as provided in Section 20 hereof.

      Section 15. Expenses.  The Secured Party shall be entitled to receive from
any proceeds of the Collateral,  the amount of any and all reasonable  expenses,
including,  in the event of default, the fees and expenses of its counsel and of
any experts and agents which the Secured Party may incur in connection  with (i)
the  administration  of this Agreement,  (ii) the custody or preservation of, or
the sale of,  collection from, or other realization upon, any of the Collateral,
(iii) the  exercise or  enforcement  of any of the rights of the  Secured  Party
hereunder,  or (iv) the  failure by any Pledgor to perform or observe any of the
provisions hereof.

      Section 16. Security  Interest  Absolute.  All rights of the Secured Party
hereunder,  the interest,  and all  obligations of Pledgor  hereunder,  shall be
absolute and unconditional irrespective of:

            (i) any lack of validity or  enforceability of the Loan Documents or
            the  Secured  Obligations  or  any  other  agreement  or  instrument
            relating to the Loan Documents or the Secured Obligations;

            (ii) any change in the time,  manner or place of  payment  of, or in
            any other term of, the Loan Documents or the Secured Obligations, or

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             FIRST AMENDED PLEDGE AND SECURITY AGREEMENT, PAGE 9
<PAGE>

            any  renewal  or  extension  of the Loan  Documents  or the  Secured
            Obligations  or any other  amendment  or waiver of or any consent to
            any  departure  from  this  Agreement  or  any  other  agreement  or
            instrument;

            (iii) any sale,  exchange,  release or  nonperfection  of any of the
            Collateral,  or any release of any guarantor or any person liable in
            any  manner  for  the   collection   of  the  Note  or  the  Secured
            Obligations,  or  any  amendment  or  waiver  of  or  consent  to or
            departure  from any  guaranty,  the Loan  Documents  or the  Secured
            Obligations; or

            (iv) any  other  circumstance  that  might  otherwise  constitute  a
            defense  available to, or a discharge of,  Pledgor in respect of any
            of the Loan Documents or the Secured Obligations.

      Section 17. Amendments and Waivers. The Loan Documents represent the final
agreement  agreed to by the parties.  No amendment or waiver of any provision of
the Loan  Documents,  and no consent by Secured  Party to any breach  thereof by
Pledgor shall in any event be effective  unless the same shall be in writing and
signed by the Secured Party,  Pledgor and, if appropriate,  any guarantor of any
Secured Obligation,  and then such waiver or consent shall be effective only for
the specific purpose for which given. No course of dealing between Pledgor,  any
guarantor of any Secured  Obligation  and Secured Party in exercising any rights
or  remedies in the Loan  Documents  shall  operate as a waiver or preclude  the
exercise of any other rights or remedies in the Loan Documents.  All such rights
and remedies shall continue unimpaired,  notwithstanding any delay, extension of
time, renewal, compromise or other indulgence granted with respect to any of the
Secured  Obligations.  Pledgor  hereby  waives  all  notice  of any such  delay,
extension of time, renewal,  compromise or indulgence,  and consents to be bound
thereby as fully and  effectually as if Pledgor  expressly had agreed thereto in
advance.  The  aforesaid  Note  may be  negotiated  by  Secured  Party,  without
releasing Pledgor or the Collateral.

      Section 18. Time is of the Essence; No Waiver:  Cumulative Remedies.  Time
and  exactitude of each of the terms,  obligations,  covenants and conditions of
this Agreement are hereby declared to be of the essence.  No failure on the part
of the Secured Party to exercise,  and no delay in exercising,  any right, power
or remedy  hereunder shall operate as a waiver thereof,  nor shall any single or
partial  exercise  of any such  right,  power or  remedy  by the  Secured  Party
preclude  any other or further  exercise  thereof or the  exercise  of any other
right,  power or remedy.  All  remedies  hereunder  are  cumulative  and are not
exclusive of any other remedies provided by law.

      Section 19. Binding Effect. This Agreement shall be binding upon and inure
to the  benefit of the parties  hereto and their  respective  heirs,  executors,
administrators,  successors  and  assigns.  The  Secured  Party may assign  this
Agreement,  and if assigned,  the assignee  shall be  entitled,  upon  notifying
Pledgor,  to the payment and  performance of all of the Secured  Obligations and
agreements of Pledgor hereunder and to all of the rights and remedies of Secured
Party hereunder,  and Pledgor will assert no claims or defenses Pledgor may have
against  Secured Party against the assignee.  The gender and number used in this
Agreement are used for reference  term only and shall apply with the same effect
whether the parties are masculine, feminine, neuter, singular or plural.

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             FIRST AMENDED PLEDGE AND SECURITY AGREEMENT, PAGE 10
<PAGE>

      Section 20.  Termination.  This Agreement shall terminate upon the payment
in full of the Note and Secured Obligations.  Upon such termination, the Secured
Party shall reassign and redeliver (or cause to be reassigned  and  redelivered)
to appropriate  Pledgor, or to such person or persons as Pledgor shall designate
or to  whomever  may be  lawfully  entitled  to receive  such  surplus,  against
receipt,  such of the  Collateral  pledged by that Pledgor (if any) as shall not
have been sold or otherwise  applied by the Secured Party  pursuant to the terms
hereof  and  shall  still be held by it  hereunder,  together  with  appropriate
instruments of reassignment and release.  Any such reassignment shall be without
recourse upon or warranty by the Secured Party and at the expense of Pledgor.

      Section 21. Addresses for Notices. Any notice or communication to be given
or made hereunder shall be in writing  (including  facsimile  communication) and
may be given or made personally or by first class letter, telefax, courier telex
or tested telex, telegram or cable (confirmed, in the case of a telecopy, telex,
telegram or cable, by a letter  delivered  personally  within,  or dispatched by
first class mail within, twenty-four (24) hours of the dispatch of such telefax,
telex, telegram or cable) and shall be effective when actually received. For the
purposes hereof,  the address of the Pledgor shall be the address  maintained in
the records of the Secured Party (until  notice of a change  thereof is given as
provided in this Section 21), and the address of the Secured Party (until notice
of a change  thereof  is given  as  provided  in this  Section  21)  shall be as
follows:

                              Value Partners, Ltd.
                                2200 Ross Avenue
                                 Suite 4660 West
                              Dallas, Texas 75201.

      Section 22.  Continuing  Security  Interest;  Assignments.  This Agreement
shall  create a continuing  security  interest in the  Collateral  and shall (i)
remain in full force and effect until termination as provided in herein, (ii) be
binding upon Pledgor,  the Secured  Party and their  respective  successors  and
assigns,  and (iii)  inure,  together  with the rights,  powers and  remedies of
Pledgor and the Secured Party hereunder,  to the benefit of Pledgor, the Secured
Party and their respective successors,  transferees and assigns, as the case may
be.

      Section 23.  Governing Law. This Agreement and the rights and  obligations
of the  parties  hereto  shall be  governed  by and  construed  and  enforced in
accordance  with the laws of the State of Texas  (other  than  conflict  of laws
rules).

      Section  24.  Severability.  Wherever  possible,  each  provision  of this
Agreement  shall  be  interpreted  in such  manner  as to be  effective.  If any
provisions of this  Agreement or any lien,  security  interest or other right of
the  Secured  Party  hereunder   shall  be  held  to  be  invalid,   illegal  or
unenforceable   under   applicable   law,   such   invalidity,   illegality   or
unenforceability  shall  not  affect  any  other  provision  herein or any lien,
security interest or other right granted hereby.

      Section 25. Usury.  All agreements  between Pledgor and the Secured Party,
whether now  existing or  hereafter  arising  and whether  written or oral,  are

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             FIRST AMENDED PLEDGE AND SECURITY AGREEMENT, PAGE 11
<PAGE>

hereby  limited  so that in no  contingency,  whether  by  reason  of  demand or
acceleration of the Final Maturity Date, as that term is defined in the Note, or
otherwise,  shall the interest contracted for, charged, received, paid or agreed
to be paid to the Secured Party exceed the maximum amount  permissible under the
laws of the State of Texas  (hereinafter  the  "Applicable  Law").  If, from any
circumstance  whatsoever,  interest  would  otherwise  be payable to the Secured
Party in excess of the maximum amount  permissible under the Applicable Law, the
interest  payable to the Secured  Party  shall be reduced to the maximum  amount
permissible  under the Applicable Law, and if from any  circumstance the Secured
Party 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 the party making such  payment.  All  interest  paid or agreed to be
paid to the Secured Party 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.  The  Secured  Party  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 Pledgor and the Secured Party.

      Section  26.  Multiple  Counterparts.  This  Agreement  may be executed in
separate or multiple  counterparts by the parties,  and all of such counterparts
shall be considered as one and the same instrument notwithstanding the fact that
various  counterparts are signed by only one or more of the parties,  and all of
such Agreements shall be deemed but one and the same Agreement.

      IN WITNESS WHEREOF, the parties hereto have executed this Agreement, as of
the date first above written.


                                    SECURED PARTY:

                                    VALUE PARTNERS, LTD.

                                    By: Fisher Ewing Partners,
                                    a Texas general partnership

                                    General Partner



                                    By: /s/Timothy Ewing
                                        ----------------------------------------
                                          Timothy Ewing
                                    Its:  General Partner


                                    PLEDGOR:



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             FIRST AMENDED PLEDGE AND SECURITY AGREEMENT, PAGE 12
<PAGE>

                                    TELENATIONAL COMMUNICATIONS, INC.

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

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





















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             FIRST AMENDED PLEDGE AND SECURITY AGREEMENT, PAGE 13
<PAGE>








                                   EXHIBIT "A"

                           SCHEDULE OF PLEDGED ASSETS

      A. All  "accounts",  as such  term is  defined  in  Article  9 of the UCC,
acquired by Pledgor  pursuant to the Asset  Purchase  Agreement,  shall include,
without  limitation,  each of the  following,  whether  now  owned or  hereafter
acquired by the Pledgor: (a) all rights of the Pledgor to payment for goods sold
or leased or services  rendered,  whether or not earned by performance,  (b) all
accounts receivable of the Pledgor, (c) all rights of the Pledgor to receive any
payment  of money or other  form of  consideration,  (d) all  security  pledged,
assigned  or granted to or held by the  Pledgor to secure any of the  foregoing,
(e)  all  guaranties  of,  or  indemnifications  with  respect  to,  any  of the
foregoing,  and (f) all rights of the  Pledgor  as an unpaid  seller of goods or
services,  including,  but not  limited  to, all rights of  stoppage in transit,
replevin,  reclamation and resale.  The total value of such accounts  subject to
this Pledge shall not exceed the present  value of such  accounts held by or for
the benefit of Pledgor as of the date hereof.

      B. All "chattel  paper",  as such term is defined in Article 9 of the UCC,
acquired by Pledgor pursuant to the Asset Purchase Agreement. The total value of
such chattel  paper shall not exceed the present  value of chattel paper held by
or for the benefit of Pledgor.

      C. All  "instruments",  as such term is  defined  in Article 9 of the UCC,
acquired by Pledgor pursuant to the Asset Purchase Agreement,  shall include all
promissory  notes,  drafts,  bills of  exchange,  and trade  acceptances  of the
Pledgor,  whether  now owned or  hereafter  acquired.  The  total  value of such
instruments shall not exceed the present value of instruments held by or for the
benefit of Pledgor.

      D. All "general intangibles",  as such term is defined in Article 9 of the
UCC,  acquired by Pledgor  pursuant to the Asset  Purchase  Agreement  and shall
include,  without  limitation,  each of the  following:  (1) all of the Pledgor=
service marks, trade names, trade secrets, registrations,  goodwill, franchises,
licenses,  permits,  proprietary  information,   customer  lists,  designs,  and
inventions;  (2) all of the  Pledgor=  books,  records,  data,  plans,  manuals,
computer software,  computer tapes,  computer disks,  computer programs,  source
codes,  object  codes,  and all rights of the Pledgor to retrieve data and other
information  from  third  parties;  (3)  all of the  Pledgor=  contract  rights,
partnership interests,  joint venture interests,  securities,  deposit accounts,
investment  accounts and certificates of deposit;  (4) all rights of the Pledgor
to payment under letters of credit and similar  agreements;  (5) all tax refunds
and tax  refund  claims of the  Pledgor,  (6) all choses in action and causes of
action of the  Pledgor  (whether  arising in  contract,  tort or  otherwise  and
whether  or not  currently  in  litigation)  and all  judgments  in favor of the
Pledgor,  (7)  all  rights  and  claims  of the  Pledgor  under  warranties  and
indemnities,  and (8) all rights of the Pledgor under any insurance,  surety, or
similar contract or arrangement.


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             FIRST AMENDED PLEDGE AND SECURITY AGREEMENT, PAGE 14
<PAGE>

      E. All  "documents",  as such  term is  defined  in  Article 9 of the UCC,
acquired by Pledgor from Telenational  pursuant to the Asset Purchase  Agreement
including, without limitation, all documents of title and all receipts covering,
evidencing or representing goods now owned or hereafter acquired by the Pledgor.

      F. All  "equipment",  as such  term is  defined  in  Article 9 of the UCC,
acquired by Pledgor from Telenational  pursuant to the Asset Purchase  Agreement
or hereafter acquired as a substitution, replacement or accession thereto by the
Pledgor,  and, in any event shall  include,  without  limitation,  all switches,
machinery,  equipment,  furniture,  fixtures, trade fixtures,  trailers, rolling
stock, vessels,  aircraft, and vehicles now owned by the Pledgor and any and all
additions,  substitutions,  and  replacement of any of the  foregoing,  wherever
located,  together  with all  attachments,  components,  parts,  equipment,  and
accessories installed thereon or affixed thereto.

      G. All  "inventory",  as such  term is  defined  in  Article 9 of the UCC,
acquired by Pledgor from Telenational  pursuant to the Asset Purchase Agreement,
and, in any event,  shall include,  without  limitation,  each of the following,
whether now owned or hereafter acquired by the Pledgor:  (l) all goods and other
personal  property  of the  Pledgor  that  are  held  for sale or lease or to be
furnished under any contract of service; (2) all raw materials, work-in-process,
finished  goods,  inventory,  supplies and  materials  of the  Pledgor;  (3) all
wrapping, packaging, advertising, and shipping materials of the Pledgor; (4) all
goods that have been  returned to,  repossessed  by or stopped in transit by the
Pledgor;  and (5) all  documents  evidencing  any of the  foregoing.  This shall
include the rights in and to the  unredeemed  value of prepaid  telephone  cards
commonly referred to as "breakage".  The total value of such inventory shall not
exceed the present value of inventory held by or for the benefit of Pledgor.

      H. All rights of Pledgor under any agreement (together with any collateral
or other security  therefor  existing at any time,  the "Assigned  Agreements"),
acquired by Pledgor from Telenational  pursuant to the Asset Purchase  Agreement
including,  without limitation,  (1) all rights of the Pledgor to receive moneys
due and to become due under or  pursuant  to the  Assigned  Agreements,  (2) all
rights of the Pledgor to receive proceeds of any insurance, indemnity, warranty,
or  guaranty  with  respect to the  assigned  Agreements,  (3) all claims of the
Pledgor  for  damages  arising  out of or for  breach  of or  default  under the
assigned Agreements,  and (4) all rights of the Pledgor to enforce and terminate
the Assigned Agreements, to performance by all obligors thereunder and to compel
performance and otherwise exercise all rights and remedies thereunder.

      I. All of the following acquired by Pledgor from Telenational  pursuant to
the  Asset  Purchase  Agreement:  (1)  all  copyrights,   works  protectable  by
copyright,  copyright registrations,  and copyright applications of the Pledgor,
if any; (2) all renewals, extensions, and modifications thereof; (3) all income,
royalties,  damages,  profits,  and payments relating to or payable under any of
the foregoing;  (4) the right to sue for past, present, or future  infringements
of any of the  foregoing;  (5) all other rights and benefits  relating to any of
the  foregoing  throughout  the  world;  and (6) all  goodwill  associated  with
symbolized by any of the foregoing; in each case, whether now owned or hereafter
acquired by the Pledgor (collectively, the "Copyrights").

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             FIRST AMENDED PLEDGE AND SECURITY AGREEMENT, PAGE 15
<PAGE>


      J.    All  written  agreements  acquired  by Pledgor  from  Telenational
pursuant to the Asset Purchase  Agreement granting to the Pledgor any right to
use any Copyright.

      K. All of the following acquired by Pledgor from Telenational  pursuant to
the  Asset  Purchase  Agreement:  (1)  all  patents,  patent  applications,  and
patentable  inventions  of the Pledgor,  if any, and all of the  inventions  and
improvements  described and claimed therein;  (2) all continuations,  divisions,
renewals, extensions, modifications,  substitutions,  continuations-in-part,  or
reissues of any of the foregoing; (3) all income,  royalties,  profits, damages,
awards, and payments relating to or payable under any of the foregoing;  (4) the
right  to  sue  for  past,  present,  and  future  infringements  of  any of the
foregoing;  (5) all other rights and benefits  relating to any of the  foregoing
throughout the world; (6) all goodwill associated with any of the foregoing;  in
each case, acquired by Pledgor from Telenational  pursuant to the Asset Purchase
Agreement (collectively, the APatents@).

      L. All written agreements  acquired by Pledgor from Telenational  pursuant
to the Asset  Purchase  Agreement  granting  to the Pledgor any right to use any
invention on which a Patent is in existence.

      M. All of the following acquired by Pledgor from Telenational  pursuant to
the Asset Purchase Agreement: (1) all trademarks,  trade names, corporate names,
company names, business names,  fictitious business names, trade styles, service
marks, logos, other business  identifiers  (including the rights and interest in
and to the use of the the logos and identifiers of any third parties which Maker
may have the right to use), prints and labels on which any of the foregoing have
appeared  or  appear,  all  registrations  and  recordings   thereof,   and  all
applications in connection therewith including  registrations,  recordings,  and
applications in the United States Patent and Trademark  Office or in any similar
office or agency of the United States, any state thereof or any other country or
any political  subdivision  thereof;  (2) all reissues,  extensions and renewals
thereof;  (3) all income,  royalties,  damages,  and  payments  now or hereafter
relating to or payable under any of the foregoing  including damages or payments
for past or future  infringements of any of the foregoing;  (4) the right to sue
for past,  present,  and future  infringements of any of the foregoing;  (5) all
rights  corresponding to any of the foregoing  throughout the world; and (6) all
goodwill  associated with and symbolized by any of the foregoing;  in each case,
whether  now owned or  hereafter  acquired  by the  Pledgor  (collectively,  the
"Trademarks").

      N.    All  written  agreements  acquired  by Pledgor  from  Telenational
pursuant  to the Asset  Purchase  Agreement  granting to the Pledgor any right
to use any Trademark.


      O. All other  goods and  personal  property  of the Pledgor of any kind or
character;  whether tangible or intangible acquired by Pledgor from Telenational
pursuant to the Asset Purchase Agreement.

      P.    Those  items  set  forth  on  Exhibit  A-1  attached   hereto  and
incorporated herein by reference.


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             FIRST AMENDED PLEDGE AND SECURITY AGREEMENT, PAGE 16
<PAGE>

      Q.    The  proceeds,  in  cash  or  otherwise,  of any  of the  property
described herein and all liens, security,  rights,  remedies and claims of the
Pledgor with respect thereto.


      R. All  "proceeds"  of the  property  described  herein,  as such  term is
defined in Section 9.306 of the UCC and, in any event, shall include, but not be
limited to; (1) any and all proceeds of any insurance,  indemnity,  warranty, or
guaranty  payable to the  Pledgor  from time to time with  respect to any of the
property  described  herein,  (2) any and all payments (in any form  whatsoever)
made or due and payable to the Pledgor from time to time in connection  with any
requisition,  confiscation,  condemnation,  seizure, or forfeiture of all or any
part of the property  described  herein,  by any governmental  authority (or any
person  or  entity  acting,  or  purporting  to  act,  for or on  behalf  of any
governmental  authority);  and (3) any and all other  amounts  from time to time
paid or payable under or in connection with any of the property described herein
and all products of the property described herein.

      As used herein,  "UCC" means the Uniform  Commercial  Code as in effect in
the  State of Texas;  provided,  that if by  mandatory  provisions  of law,  the
perfection or effect of perfection or non-perfection of the security interest in
any  Collateral  to which this  document  relates  is  governed  by the  Uniform
Commercial  Code  as in  effect  on or  after  the  date  hereof  in  any  other
jurisdiction,  UCC means the Uniform  Commercial Code as in effect in such other
jurisdiction  for purposes of the provisions  hereof relating to such perfection
or the effect of perfection or non-perfection.


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             FIRST AMENDED PLEDGE AND SECURITY AGREEMENT, PAGE 17
<PAGE>





                                    EXHIBIT B

                            SCHEDULE OF ENCUMBRANCES



Secured Party:    BA Credit Corporation
Security:         Equipment, Product, Proceeds
Filed:            6-1-93


Secured Party:    Harris Corporation
Security:         Equipment
Filed:            12-2-94


Secured Party:    Bank of Nebraska
Security:         Equipment, Product
Filed:            4-10-95


Secured Party:    Business Leasing, Inc.
Security:         Equipment
Filed:            6-17-96


Secured Party:    Paul F. Schneider
Security:         Accounts receivable on Telenational's customer base.
Filed:            8-12-96


Secured Party:    Midcom Communications, Inc.
Security:         Accounts receivable, inventory, equipment, general intangibles
                  and all other personal property.
Filed:            12-13-96

Secured Party:    Value Partners, Ltd.
Security:         Collateral, as defined in this Agreement.
Filed:            March 24, 1997


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             FIRST AMENDED PLEDGE AND SECURITY AGREEMENT, PAGE 18