EXHIBIT 10.37


                   AMENDMENT OF REGISTRATION RIGHTS AGREEMENT
                                   (The Trust)


     THIS AMENDMENT OF  REGISTRATION  RIGHTS  AGREEMENT  (this  "Amendment")  is
entered into as of the 18 day of March, 1999, by and among TEL-SAVE.com, INC., a
Delaware corporation (the "Company"), and MARK PAVOL, as Trustee of that certain
D&K Grantor Retained Annuity Trust dated June 15, 1998 (the "Trust").

                                    RECITALS:

     A. The parties hereto and DANIEL M. BORISLOW,  a former director,  officer,
and shareholder of the Company ("Borislow"), and SETH TOBIAS, as Trustee of that
certain D&K Grantor Retained Annuity Trust II dated August 18, 1998 ("Trust II")
have  entered  into  that  certain  Registration  Rights  Agreement  dated as of
December 31, 1998 (the "Registration Rights Agreement").

     B. The parties  hereto,  Borislow,  and certain  other parties have entered
into that  certain  Agreement  dated  March 15,  1999,  pertaining,  among other
things, to the modification of certain promissory notes issued by Communications
TeleSystems  International,  and it is a condition  to that  Agreement  that the
parties hereto agree to enter into this Amendment.

     C. The  Company,  Borislow,  and  Trust  II have  entered  into a  separate
Amendment of Registration Rights Agreement (Borislow and Trust II).

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

     1.  Definitions.  Terms in this Agreement with initial  capital letters and
not otherwise  defined herein shall have the meanings  defined for such terms in
the Registration Rights Agreement.

     2. Amendment of Section 7(a) of the Registration Rights Agreement.  Section
7(a) of the  Registration  Rights Agreement is hereby amended to read in full as
follows:

          "(a) The  Company  agrees  that in the event that it makes a public or
          private  offering of its debt  securities in exchange for cash, to the
          extent  permitted by law the Company  will, at the option of the Trust
          (subject  to the terms  stated  herein),  utilize up to forty  percent
          (40%) of the net cash  proceeds of that  offering to the Company after
          payment of the expenses  relating to the offering that are to be borne
          by the Company (the "Net Cash  Proceeds")  to  repurchase at then fair
          market value convertible  subordinated notes of the Company then owned
          of record


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          and beneficially by the Trust;  provided,  however, that the rights of
          the Trust  hereunder  are  subject  and  subordinate  to the rights of
          Borislow and Trust II under Section 2 of the Amendment of Registration
          Rights  Agreement  (Borislow  and Trust  II),  which  Section 2 amends
          Section 7(a) of the  Registration  Rights Agreement as to Borislow and
          Trust  II.  To the  extent  that any Net Cash  Proceeds  remain  after
          Borislow's exercise or failure to exercise timely his option set forth
          in  Section  2 of  the  Amendment  of  Registration  Rights  Agreement
          (Borislow  and Trust II) and after  Trust II's  exercise or failure to
          exercise  timely its option set forth in Section 2 of the Amendment of
          Registration  Rights Agreement  (Borislow and Trust II), the Trust may
          exercise  its  rights  under this  Section  7(a) to the extent of such
          remaining  balance of Net Cash  Proceeds.  The Trust may  exercise its
          option  set forth in this  Section  7(a) by  delivering  notice to the
          Company within five (5) days after the receipt by the Trust of written
          notice  from the  Company,  such  notice to be sent by  Registered  or
          Certified Mail with Return Receipt Requested, that the Company intends
          to make a  public  or  private  offering  of its  debt  securities  in
          exchange for cash.  Notwithstanding  the foregoing,  this Section 7(a)
          shall  not  apply to any debt  offering  by the  Company  to a bank or
          financial institution or in a commercial context."

     3. Amendment of Section 7(d) of the Registration Rights Agreement.  Section
7(d) of the  Registration  Rights Agreement is hereby amended to read in full as
follows:

          "(d) If, during the period  commencing  March 18, 1999,  and ending on
          the close of business on September 17, 2000 (the "Time  Period"),  the
          Company  shall sell any shares of its  capital  stock  (including  its
          Common  Stock)  in  connection  with  any  employee  benefit  plan  or
          stockholder  rights  distribution,  up to the entire proceeds from the
          sale of  shares  in  connection  with such  employee  benefit  plan or
          stockholder  rights  distribution  ("Sale  Proceeds")  during the Time
          Period  shall be used,  at the  Trust's  option  and if  permitted  by
          applicable  law and as  provided  in this  Section  7(d),  to purchase
          Common  Stock  then owned by the Trust;  provided,  however,  that the
          rights  of  the  Trust  under  this   Section  7(d)  are  subject  and
          subordinate to the rights of Borislow under Section 3 of the Amendment
          of  Registration  Rights  Agreement  (Borislow  and Trust  II),  which
          Section 3 amends Section 7(d) of the Registration  Rights Agreement as
          to  Borislow.  To the  extent  that any  Sale  Proceeds  remain  after
          Borislow's exercise or failure to


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<PAGE>

          exercise  timely his option set forth in Section 3 of the Amendment of
          Registration  Rights Agreement  (Borislow and Trust II), the Trust may
          exercise its rights under this Section 7(d).

               "(i) The Trust may exercise its option by giving  timely  written
          notice of such exercise to the Company. Such notice shall be timely if
          it is received  by the Company  within five (5) days after the receipt
          by the Trust of a written Quarterly Notice (hereinafter  defined) sent
          to the Trust by  Registered  or  Certified  Mail with  Return  Receipt
          Requested.

               "(ii) The Company  agrees to give the Trust written notice within
          five (5) calendar days  following the end of each calendar  quarter of
          the  amount of any Sale  Proceeds  as to which the option set forth in
          this Section 7(d) shall remain unterminated at the time of such notice
          and after Borislow's exercise or failure to exercise timely his option
          in  Section  3 of  the  Amendment  of  Registration  Rights  Agreement
          (Borislow  and Trust  II),  such  notice to be sent by  Registered  or
          Certified Mail with Return Receipt Requested (the "Quarterly Notice").
          The Trust's  option set forth in this Section 7(d) shall  terminate as
          to any Sale  Proceeds  as to which  the  Trust  shall  have  failed to
          exercise its option pursuant to a proper Quarterly Notice.

               "(iii) The purchase price of any Common Stock purchased  pursuant
          to an option  exercised in response to a Quarterly Notice shall be the
          average of the daily  closing  prices (or of the closing bid and asked
          prices) for the last ten (10)  trading  days of the  calendar  quarter
          then most  recently  ended with respect to Common Stock that is listed
          on a national  securities  exchange or traded on the  over-the-counter
          market or quoted on NASDAQ."

               "(v) The  valuation  of the Common  Stock and the  closing of the
          purchase  and sale shall take place as  expeditiously  as  practicable
          after  the  exercise  by the  Trust of its  option  set  forth in this
          Section 7(d)."

     4. Amendment of Section 7(e) of the Registration Rights Agreement.  Section
7(e) of the  Registration  Rights Agreement is hereby amended to read in full as
follows:


          "(e)  The  Company  agrees  to  make  available  to  the  Trust,  upon
          reasonable written notice from Trust, in connection


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<PAGE>


          with one (1)  securities  offering to be made by the Trust on or prior
          to June 30, 2000, the following  Company employees to participate in a
          standard  securities  offering "road show" of not longer than ten (10)
          days' duration regarding that offering: the Chief Executive Officer of
          the Company; and certain other appropriate employees of the Company as
          designated by such Chief Executive Officer;  provided,  however,  that
          the  rights of the Trust  under  this  Section  7(e) are  subject  and
          subordinate to the rights of Borislow under Section 4 of the Amendment
          of  Registration  Rights  Agreement  (Borislow  and Trust  II),  which
          Section 4 amends Section 7(e) of the Registration  Rights Agreement as
          to  Borislow,  and the  Trust's  rights  under this  Section  7(e) are
          subject to the condition  precedent that Borislow waive in writing his
          rights  under  Section  4 of  the  Amendment  of  Registration  Rights
          Agreement  (Borislow and Trust II); and, provided  further,  that such
          Borislow  waiver shall not be a condition to the exercise by the Trust
          of its  rights  under  this  Section  7(e) if,  at the time the  Trust
          exercises  such  rights,  Borislow  does not own any  shares of Common
          Stock.  The Company may delay such  participation  if the time of such
          participation requested by the Trust would cause undue hardship on the
          Company;  in the event of such a delay,  the June 30,  2000,  date set
          forth above in this Scetion 7(e) shall be extended by one day for each
          day  of  such  delay.   The  Company  shall  pay  for  the  reasonable
          out-of-pocket  expenses  incurred by the  Company and its  officers in
          complying with this Section."

     5.   Miscellaneous.

          (a) Each of the parties hereto  represents and warrants to, and agrees
with,  each of the other  parties  hereto  that,  at the date  hereof:  (i) such
representing  and  warranting  party is not in  default  under the  Registration
Rights  Agreement;  (b)  such  party  has not  suffered  any  damage  under  the
Registration  Rights  Agreement and has no cause of action,  right of set-off or
counterclaim,  or any other  claim of any nature  whatsoever  against any of the
other parties hereto or any director,  officer,  attorney,  agent,  employee, or
affiliate of any of such other parties under the  Registration  Rights Agreement
or otherwise  (collectively,  "Claims");  and (c) such party  hereby  waives and
relinquishes  any and all  Claims.  Each such  party  further  hereby  agrees to
indemnify  and hold  harmless  each of the other  parties  and their  respective
officers, directors,  attorneys, agents, employees, and affiliates harmless from
any loss,  damage,  judgment,  liability,  and expense  (including counsel fees)
suffered by or rendered  against the other  parties or any of them on account of
anything arising out of the Registration  Rights Agreement,  this Amendment,  or
any other document delivered pursuant hereto.


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<PAGE>

          (b) Except as expressly  modified by this Amendment,  the Registration
Rights Agreement continues in full force and effect.

     IN WITNESS WHEREOF,  the undersigned have executed this Amendment as of the
day and year first above written.



                                     Tel-Save.com, Inc.
Witness

                                   By:
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Aloysius T. Lawn, Secretary        Name:
                                   Title:





                                   ---------------------------------
Address:                           The Trust


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                                   Mark Pavol, as Trustee of that certain D&K
                                   Grantor Retained Annuity Trust dated June 15,
                                   1998



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