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Exhibit 10.106c


                             STOCK PLEDGE AGREEMENT

                                                           Date: April 11, 2003

TO :     VERTICAL COMPUTER SYSTEMS, INC.


PLEDGE OF STOCK

         To induce you,  Vertical  Computer  Systems,  Inc.,  to sell  3,000,000
shares of common  stock of TranStar  Systems,  Inc.  (the  "TranStar")  for U.S.
$250,000.00 to me, Mike Radlovic, an individual ("Radlovic"), as evidenced by my
Promissory  Note, and the Loan and Security  Agreement,  by and between Radlovic
and you (the "Security Agreement"),  in that amount dated the date of this Stock
Pledge Agreement (the "Agreement"),  bearing interest at the rate of ten percent
(10%) per annum, and payable to your order on April 11, 2007 (the "Note",  which
term will include any amendments  thereto and  substitutions  therefor),  and in
consideration  of your  making said sale,  and to secure  payment of all amounts
owing  under  the Note and this  Agreement  and  performance  of all of my other
obligations  under the Note and under this  Agreement,  the  undersigned  hereby
pledge to you and grant you a  security  interest  in FIVE  MILLION  (5,000,000)
shares , with a par value of U.S. $.01 per share, of TranStar common stock owned
by       Radlovic,        represented        by        certificate(s)        no.
________________________________________________  delivered to you herewith duly
endorsed in blank or with stock powers duly signed in blank, in either case with
signatures  guaranteed by a commercial  bank in the United States or by a member
firm of the NASD or any regional or national stock exchange;  and (ii) any other
"Collateral" (as hereinafter defined).

DEFINITION OF COLLATERAL

         The term  "Collateral"  means (i) the shares of stock pledged under the
foregoing  paragraph  (collectively  called  the  "Stock"),  and (ii) any  cash,
securities or other property paid or otherwise  distributed on, with respect to,
or in exchange for any Collateral. You may at any time transfer the Stock or any
other  Collateral  into your name or the name of your nominee.  If I receive any
such other  Collateral,  I shall  promptly  deliver  the same to you in the form
received  together with any  endorsement or instrument of transfer  requested by
you; but until a "default under this Agreement" (as hereinafter defined) occurs,
I will be entitled to retain regular,  periodic dividends paid on the Stock (but
not on any other  Collateral) from the earnings of TranStar;  and you will remit
to me any such dividends which you receive. In addition, if a default under this
Agreement  occurs,  you  shall be  entitled  to vote  the  Stock  and any  other
Collateral held by you under this  Agreement,  and at all such times I shall not
be entitled to vote the Stock or any other Collateral; and I hereby grant you an
irrevocable proxy to so vote the Stock and any other Collateral.

WARRANTIES

         I hereby warrant to you that:

         a.       TranStar, Inc. is duly incorporated and validly existing under
                  the laws of the State of Nevada;

         b.       I have taken all necessary  corporate  action to authorize the
                  execution,  delivery and performance of this Agreement and the
                  Note, which constitute my legally binding obligations;

         c.       I am the sole owner of the Stock;

         d.       the Stock is validly issued, is fully paid and non-assessable,
                  and is not  subject to any claim,  restriction,  lien or other
                  encumbrance except as provided in this Agreement;

         e.       the Stock represents 29% of the total of 17,000,000  shares of
                  TranStar,  which are issued and  outstanding  and I may pledge
                  and grant a security  interest in the Stock without  obtaining
                  the approval of any other person, corporation, partnership, or
                  other entity, or any governmental authority,

                         STOCK PLEDGE AGREEMENT-RADLOVIC

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         f.       there are no options,  warrants,  privileges  or other  rights
                  outstanding  with  respect to any of the Stock  subject to the
                  terms of the Amended Stockholder's Agreement dated October 14,
                  2000.

PROHIBITION ON TRANSFER OF COLLATERAL

         I agree that I will not sell,  transfer,  assign or encumber  any of my
rights  in  any  of the  Collateral  or  grant  any  rights  in or to any of the
Collateral except pursuant to this Agreement.

FURTHER ASSURANCES

         I will,  at my  expense,  take or  cause to be taken  such  action  and
execute  and  deliver or cause to be  executed  and  delivered  such  additional
agreements and documents as you may request in connection with this Agreement or
any of  the  Collateral  or to  perfect  your  security  interest  in any of the
Collateral,  including, without limitation, delivering any Collateral to you and
executing and filing financing and other statements under the Uniform Commercial
Code in  effect  in any  state;  and I  hereby  authorize  you to sign  any such
agreement or document or  statement on my behalf and to file any such  statement
with or without my signature.


DEFAULT

         Upon a default  under  any of the  provisions  of the  Note,  or if any
warranty  by me  hereunder  is  incorrect,  or if I fail  to  perform  any of my
obligations  under this  Agreement  (any such  default or breach of  warranty or
failure being herein called "a default under this Agreement"),  you may, without
notice,  take such action as you deem advisable with respect to the  Collateral,
including,  without  limitation,  selling  any of the  Collateral  at  public or
private sale on such terms as you deem appropriate;  and you are also authorized
as my attorney-in-fact to endorse or otherwise effect the transfer of any of the
Collateral. At any such sale you may be the purchaser.

REMEDIES; ORDER OF PURSUIT

         You shall not be  required to resort to or pursue any of your rights or
remedies  under or with respect to any other  agreement or any other  collateral
before  pursuing any of your rights or remedies  under this  Agreement.  You may
pursue your rights and remedies in such order as you determine, and the exercise
by you of any right or remedy will not preclude your  exercising any other right
or remedy.

DELAY; WAIVER

         The failure or delay by you in exercising any of your rights  hereunder
or with  respect to the Note or any other  collateral  securing  the Note in any
instance shall not  constitute a waiver  thereof in that or any other  instance.
You may waive your rights only by an instrument in writing signed by you.

EXPENSES

         I agree to pay on demand all expenses of enforcing  the  provisions  of
this Agreement and your rights against any of the Collateral, including, without
limitation,  expenses  and fees of legal  counsel,  court  costs and the cost of
appellate proceedings.

WHERE TO MAKE PAYMENTS

         All payments under this Agreement  shall be made in lawful  currency of
the United States of America in immediately available funds at VERTICAL COMPUTER
SYSTEMS, INC., 6336 Wilshire Boulevard,  Los Angeles,  California,  90048, attn:
President,  as provided in the Security Agreement, or in such other manner or at
such other place as you shall designate in writing.

GOVERNING LAW; AGENT FOR SERVICE OF PROCESS

                         STOCK PLEDGE AGREEMENT-RADLOVIC

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         This  Agreement and your rights and my obligations  hereunder  shall be
governed by and construed in accordance with the law of the State of California.
I agree that any legal action or  proceeding  with respect to this  Agreement or
any of the  Collateral  may be brought in the courts of the State of  California
and of the United  States having  jurisdiction  in the County of Los Angeles and
State of California  and for the purpose of any such legal action or proceeding,
I hereby submit to the  non-exclusive  jurisdiction of such courts and agree not
to raise and waive any objection I may have based upon personal  jurisdiction or
the venue of any such  court or forum non  conveniens.  I agree not to bring any
action  or  other  proceeding  with  respect  to  this  Agreement  or  any of my
obligations  under this  Agreement  in any other court unless such courts of the
State of  California  and of the United States  determine  that they do not have
jurisdiction  in the matter.  For  purposes  of any  proceeding  involving  this
Agreement, I hereby irrevocably appoint Gary Blum, Esq., at 3278 Wilshire Blvd.,
Ste. 603 Los Angeles,  CA 90010,  my agent to receive  service of process for me
and on my behalf.

         I will at all times maintain an agent to receive  service of process in
California,  on my behalf with respect to this Agreement, and in the event that,
for any reason,  the agent named  above or any  successor  agent shall no longer
serve as my agent to receive service of process in California,  I shall promptly
appoint a successor and advise you thereof.

AMENDMENT

         This  Agreement may only be amended by an instrument in writing  signed
by you and me.


                                Very truly yours,

                                 PLEDGOR

                                  MIKE RADLOVIC

                                 -------------------------------------------
                                 By: Mike Radlovic, an individual

                                 PLEDGEE

                                 AGREED:
                                 VERTICAL COMPUTER SYSTEMS, INC.


                                 -------------------------------------------

                                 By: Richard Wade, President


                         STOCK PLEDGE AGREEMENT-RADLOVIC

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