FIRST AMENDMENT TO LETTER AGREEMENT


         This First  Amendment to the Letter  Agreement  dated January 14, 1999,
(the "Letter  Agreement")  by and among  Summus,  Ltd.,  a Delaware  corporation
("Summus,  Ltd.");  Summus  Technologies,  Inc., a Delaware corporation ("Summus
Technologies");  Brad Richdale;  and High Speed Net  Solutions,  Inc., a Florida
corporation  ("High  Speed");  is made  and  entered  into as of the 16th day of
August, 1999.

1.       The Letter Agreement is hereby amended as follows:

         A.     The last two sentences of Paragraph 4 are hereby amended to read
                in their entirety as follows:

                           Following the merger,  Net  Solutions  shall have the
                           right to appoint  two  designees  to serve on a seven
                           member  board.   If  the  Board  is  increased,   Net
                           Solutions  will retain the equivalent of 18% (rounded
                           up) representation on the Board.

         B.     Paragraph 5 of the Letter Agreement is hereby amended to read in
                its entirety as follows:

                           Within one year from April 14,  1999,  Net  Solutions
                           agrees to deliver a $2.5 Million factorable  Purchase
                           Order  that  is  satisfactory  to  Summus,  Ltd.  for
                           products of Summus,  Ltd. the specifications of which
                           will be mutually agreed upon by you and Summus,  Ltd.
                           Upon your execution of this  agreement,  you received
                           148,182 common shares of Summus  Technologies,  which
                           equalled  3% of the  issued  and  outstanding  common
                           shares  of Summus  Technologies  at that  time.  Upon
                           delivery of the purchase order to Summus Ltd. and its
                           acceptance,  which will not be unreasonably withheld,
                           by Bjorn Jawerth,  as the President of Summus,  Ltd.,
                           you will receive  additional common shares of Summus,
                           Ltd.  up to  60,000  of the  issued  and  outstanding
                           common shares of Summus, Ltd. as cash is received for
                           the purchase of products under this Purchase Order at
                           a rate  of  10,000  shares  per  $416,666.66.  (These
                           60,000  shares are  intended to  represent  6% of the
                           issued  and  outstanding   shares  of  Summus,   Ltd.
                           immediately  following the merger of Summus, Ltd. and
                           Summus  Technologies,  Inc.) If the above  referenced
                           shares  are not issued in  accordance  with the terms
                           hereof,   then  Brad  Richdale  (and  his  designees)
                           specifically  do not  waive any  rights  they now may
                           have with respect to their existing  ownership  claim
                           thereto.
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         2.       This Amendment shall become  effective upon the  consummatio
                  of the merger of Summus, Ltd. and Summus Technologies.  If the
                  merger is not  consummated,  then this Amendment shall be null
                  and void and of no force or effect.

         3.       Except as otherwise specifically modified herein the remaining
                  terms of the Letter  Agreement,  as amended,  shall  remain in
                  full force and effect.

         IN WITNESS WHEREOF, the parties have signed this First Amendment to the
Letter Agreement as of the date first above written.


                                                     SUMMUS, LTD.


                                                     By:   /s/ Bjorn Jawerth
                                                     Its:   President




                                               SUMMUS TECHNOLOGIES, INC.


                                               By:   /s/ Bjorn Jawerth
                                               Its:   President




                                               HIGH SPEED NET SOLUTIONS, INC.



                                               By:_______________________
                                               Its:______________________




                                               _____________________________
                                                     Brad Richdale