INFINITY INVESTORS, LTD.
                            SEACREST CAPITAL LIMITED
                               27 Wellington Road
                                  Cork, Ireland



                                  July 31, 1996



VIA FACSIMILE - 441/292-5560

Intelect Communications Systems Limited
Reid House, 31 Church Street
Hamilton, Bermuda

Attention:  Peter G. Leighton

         Re:      Amendment of Convertible Securities Agreement and
                  Debentures Issued Thereunder

Gentlemen:

         Reference  is  hereby  made  to  that  certain  Convertible  Securities
Agreement of Intelect  Communications  Systems  Limited  dated June 7, 1996 (the
"Subscription  Agreement") by and among Intelect  Communications Systems Limited
("Intelect"), Infinity Investors, Ltd. ("Infinity") and Seacrest Capital Limited
("Seacrest") (Infinity and Seacrest being collectively referred to as "Buyers"),
pursuant to which Buyers  subscribed  for an  aggregate of $5 million  principal
amount of  Debentures  convertible  into shares of common stock of Intelect (the
"Debentures").  Pursuant to Section 6 of the  Subscription  Agreement,  Intelect
granted Buyers a right of first refusal on certain private financings offered by
Intelect.  Intelect  has  disclosed to Buyers its desire to  consummate,  within
seven (7) business days of the date hereof (the  "Termination  Date"), a private
placement  of up to  $10  million  aggregate  principal  amount  of  convertible
debentures  on terms  substantially  as  previously  described  to  Buyers  (the
"Disclosed  Financing").  Intelect has requested  that Buyers waive its right of
first  refusal with respect to the  Disclosed  Financing.  Buyers are willing to
provide such waiver on the terms hereafter described.  Accordingly, Intelect and
Buyers  hereby agree as follows  (which  agreements,  to the extent  applicable,
shall represent an amendment to the Subscription Agreements and the Debentures):

         1. Buyers  hereby  waive their right of first  refusal as  described in
Section 6 of the Subscription Agreement with respect to the Disclosed Financing,
provided the Disclosed Financing is consummated prior to the Termination Date.









Intelect Communications Systems Limited
July 31, 1996
Page 2


         2.       Buyers and Intelect hereby amend the second sentence of
Section 3.1(b) of each Debenture to be and read in its entirety
as follows:

                  "All or any portion of the  Debenture  is  convertible  at any
                  time, and from time to time, as follows: (i) One-half (1/2) of
                  the principal  balance of all  Debentures  issued to Holder as
                  described  in  Section  7.1  hereafter  shall  be  convertible
                  beginning  on the  earlier  to occur of  August 9, 1996 or the
                  date the securities and Exchange Commission declares effective
                  that certain Registration Statement on Form S-3 of the Company
                  filed with the Securities and Exchange  Commission on or about
                  July 29, 1996 (such earlier to occur date being referred to as
                  the "Trigger Date"),  and (ii) the final one-half (1/2) of the
                  principal  balance of all such Debentures issued to the Holder
                  shall be  convertible  beginning  thirty  (30) days  after the
                  Trigger Date."

         3. Intelect and Buyers agree to amend their  agreements  concerning the
Future  Transaction (as define din Section 6 of the  Subscription  Agreement) as
follows:  commencing  October 1 and  terminating  October 20, 1996 (the  "Option
Period"),  Intelect  shall  have the  option  (the  "Call")  to cause  Buyers to
consummate the Future Transaction,  and Buyers shall have the option (the "Put")
to require Intelect to accept  consummation of the Future  Transaction,  in each
case  on  substantially  identical  terms  as  set  forth  in  the  Subscription
Agreement;  provided,  Intelect  may refuse to accept a Put  exercised by Buyers
during the Option Period if (A) on or before  October 1, 1996 Intelect has filed
with the Commission a registration  statement for the issuance of debt or equity
securities for at least $10,000,000 in aggregate  proceeds to Intelect which has
not been  withdrawn  and which  offering is to be  underwritten  by a nationally
recognized  investment  banking firm (the  "Underwriter") on customary terms and
conditions, and (B) the Underwriter has delivered written notice to Intelect and
Buyers that the exercise of the Put will  materially  and  adversely  affect the
ability of Intelect to consummate such underwritten offering.

         4. Intelect and Buyers agree to correct a typographical error such that
all references to "Seacrest"  Capital Limited in the Subscription  Agreement and
the Debentures are hereby changed to "Seacrest" Capital Limited.

         5.  Except  as  described  herein,  the  terms  and  provisions  of the
Subscription  Agreement and each  Debenture are ratified and confirmed and shall
continue in full force and effect.






Intelect Communications Systems Limited
July 31, 1996
Page 3


         6.  Intelect  and each Buyer  agrees  that at any time and from time to
time, upon written request,  it shall execute and deliver such further documents
and do such  further  acts and  things as the  requesting  party may  reasonably
request in order to fully effect the purchase of this letter agreement.

         7.  From and  after the date that  Intelect  and the  Buyers  each have
executed  this  agreement,  references  in the  Subscription  Agreement  and the
Debentures to the Subscription Agreements and the Debentures shall refer to such
agreement as amended hereby.  Intelect  further agrees that each certificate for
Debentures  issued on or after  the date  hereof  (whether  for  exchange  or in
connection with a partial conversion of the Debentures) shall be issued with the
provisions of Section 3.1(b)  reflecting the amendment to such Section set forth
herein.

         To evidence your agreement with the foregoing,  please countersign this
letter in the space provided  below.  This letter may be executed in one or more
counterparts and by facsimile signature.

                                             Yours very truly,



                                             SEACREST CAPITAL LIMITED


                                             By:/s/ James E. Martin
                                               ----------------------------

                                             Title: President and Director
                                                  -------------------------

                                             INFINITY INVESTORS, LTD.


                                             By:/s/ J.A. Loughran
                                               ----------------------------

                                             Title: Director
                                                  -------------------------


ACKNOWLEDGED AND AGREED TO:

INTELECT COMMUNICATIONS SYSTEMS LIMITED


By:/s/ Peter G. Leighton
  --------------------------
Title: President
     -----------------------