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Exhibit 10.103b



THIS DEBENTURE,  AND THE SECURITIES INTO WHICH IT IS CONVERTIBLE  (COLLECTIVELY,
THE  "SECURITIES"),  HAVE NOT BEEN REGISTERED WITH THE UNITED STATES  SECURITIES
AND  EXCHANGE  COMMISSION  OR  THE  SECURITIES  COMMISSION  OF  ANY  STATE.  THE
SECURITIES ARE BEING OFFERED PURSUANT TO A SAFE HARBOR FROM  REGISTRATION  UNDER
REGULATION  D  PROMULGATED  UNDER THE  SECURITIES  ACT OF 1933,  AS AMENDED (THE
"ACT").  THE SECURITIES ARE  "RESTRICTED"  AND MAY NOT BE OFFERED OR SOLD UNLESS
THE  SECURITIES  ARE  REGISTERED  UNDER THE ACT,  PURSUANT  TO  REGULATION  D OR
PURSUANT TO AVAILABLE  EXEMPTIONS FROM THE REGISTRATION  REQUIREMENTS OF THE ACT
AND THE  COMPANY  WILL BE  PROVIDED  WITH  OPINION  OF  COUNSEL  OR  OTHER  SUCH
INFORMATION  AS IT MAY  REASONABLY  REQUIRE TO CONFIRM THAT SUCH  EXEMPTIONS ARE
AVAILABLE. FURTHER HEDGING TRANSACTIONS INVOLVING THE SECURITIES MAY NOT BE MADE
EXCEPT IN COMPLIANCE WITH THE ACT.



                                    DEBENTURE


                         VERTICAL COMPUTER SYSTEMS, INC.


                            5% CONVERTIBLE DEBENTURE


                               DUE APRIL 14, 2006


No.  ___                                                          $__________

         This Debenture is issued by VERTICAL COMPUTER SYSTEMS, INC., a Delaware
corporation (the "COMPANY"), to ____________________________  (together with its
permitted  successors  and assigns,  the "HOLDER")  pursuant to exemptions  from
registration under the Securities Act of 1933, as amended.

                                   ARTICLE I.

         SECTION 1.01 PRINCIPAL AND INTEREST.  For value received,  on April 14,
2003,  the Company  hereby  promises to pay to the order of the Holder in lawful
money of the United  States of America and in  immediately  available  funds the
principal sum of __________________(US $________), together with interest on the
unpaid  principal  of this  Debenture  at the rate of five percent (5%) per year
(computed on the basis of a 365-day year and the actual days  elapsed)  from the
date of this Debenture until paid. At the Company's option, the entire principal
amount and all  accrued  interest  shall be either (a) paid to the Holder on the
second  (2nd)  year  anniversary  from  the  date  hereof  or (b)  converted  in
accordance with Section 1.02 herein.





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         SECTION 1.02 OPTIONAL  CONVERSION.  Commencing one hundred twenty (120)
days after the date hereof,  the Holder is entitled,  at its option, to convert,
and sell on the same day,  at any time and from time to time,  until  payment in
full  of  this  Debenture,  all  or any  part  of the  principal  amount  of the
Debenture,  plus accrued interest,  into shares (the "CONVERSION SHARES") of the
Company's  common stock,  par value $0.001 per SHARE  ("COMMON  STOCK"),  at the
price per share (the "CONVERSION PRICE") equal to the lesser of (a) $0.03 or (b)
an amount equal to eighty  percent (80%) of the lowest  Closing Bid Price of the
Common Stock for the five (5) trading days immediately  preceding the Conversion
Date (as  defined  herein).  Subparagraphs  (a) and (b) above  are  individually
referred to as a "CONVERSION  PRICE". As used herein,  "PRINCIPAL  MARKET" shall
mean The National  Association  of Securities  Dealers  Inc.'s  Over-The-Counter
Bulletin Board,  Nasdaq  SmallCap  Market,  or American Stock  Exchange.  If the
Common  Stock is not traded on a Principal  Market,  the Closing Bid Price shall
mean, the reported  Closing Bid Price for the Common Stock,  as furnished by the
National Association of Securities Dealers, Inc., for the applicable periods. No
fraction of shares or scrip  representing  fractions of shares will be issued on
conversion,  but the number of shares  issuable  shall be rounded to the nearest
whole share. To convert this Debenture,  the Holder hereof shall deliver written
notice thereof, substantially in the form of EXHIBIT "A" to this Debenture, with
appropriate  insertions (the "CONVERSION NOTICE"), to the Company at its address
as set forth herein.  The date upon which the conversion shall be effective (the
"CONVERSION  DATE")  shall be deemed  to be the date the  Company  receives  the
Conversion Notice.

         SECTION 1.03 RESERVATION OF COMMON STOCK. The Company shall reserve and
keep available out of its authorized but unissued shares of Common Stock, solely
for the purpose of effecting the  conversion of this  Debenture,  such number of
shares of Common Stock as shall from time to time be  sufficient  to effect such
conversion, based upon the Conversion Price. If at any time the Company does not
have a sufficient number of Conversion Shares authorized and available, then the
Company shall call and hold a special meeting of its stockholders  within thirty
(30)  days of that  time  for the sole  purpose  of  increasing  the  number  of
authorized shares of Common Stock.

         SECTION 1.04 RIGHT OF REDEMPTION.  The Company at its option shall have
the right to redeem,  with thirty (30) business days advance written notice (the
"REDEMPTION NOTICE"), a portion or all outstanding  convertible  debenture.  The
redemption  price  shall be one  hundred  twenty  percent  (120%) of the  amount
redeemed plus accrued interest.

         SECTION 1.05 REGISTRATION  RIGHTS. The Company is obligated to register
the  resale of the  Conversion  Shares  under  the  Securities  Act of 1933,  as
amended,  pursuant to the terms of a Registration Rights Agreement,  between the
Company and the Holder of even date herewith (the "INVESTOR  REGISTRATION RIGHTS
AGREEMENT").

         SECTION 1.06 INTEREST PAYMENTS. The interest so payable will be paid by
the  Company  in cash  (via wire  transfer  or  certified  funds) at the time of
maturity or conversion to the person in whose name this Debenture is registered.
In the event of default, as described in Article III Section 3.01 hereunder, the
Holder  may  elect  that the  interest  be paid in the form of  Common  Stock as
provided  for in the  Irrevocable  Transfer  Agent  Instructions  of  even  date
herewith.  If paid in the form of Common Stock, the amount of stock to be issued
will be calculated  as follows:  the value of the stock shall be the Closing Bid
Price on: (i) the date the interest payment is due; or (ii) if the interest

                                        2


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payment is not made when due, the date the interest payment is made. A number of
shares of Common Stock with a value equal to the amount of interest due shall be
issued.  No fractional shares will be issued;  therefore,  in the event that the
value of the Common Stock per share does not equal the total  interest  due, the
Company will pay the balance in cash.

         SECTION 1.07 PAYING AGENT AND  REGISTRAR.  Initially,  the Company will
act as paying  agent and  registrar.  The Company  may change any paying  agent,
registrar,  or  Company-registrar  by giving  the  Holder not less than ten (10)
business  days' written  notice of its election to do so,  specifying  the name,
address, telephone number and facsimile number of the paying agent or registrar.
The Company may act in any such capacity.

         SECTION 1.08 SUBORDINATED  NATURE OF DEBENTURE.  This Debenture and all
payments  hereon,  including  principal or interest,  shall be  subordinate  and
junior in right of payment to all  accounts  payable of the Company  incurred in
the  ordinary  course of business  and/or bank debt of the Company not to exceed
$200,000.

                                   ARTICLE II.

         SECTION 2.01 AMENDMENTS AND WAIVER OF DEFAULT. The Debenture may not be
amended without the consent of the Holder.  Notwithstanding  the above,  without
the consent of the Holder,  the Debenture may be amended to cure any  ambiguity,
defect or  inconsistency,  or to make any change that does not adversely  affect
the rights of the Holder.

                                  ARTICLE III.

         SECTION  3.01  EVENTS OF  DEFAULT.  An Event of  Default  is defined as
follows:  (a) failure by the Company to pay amounts due hereunder within fifteen
(15) days of the date of maturity of this Debenture;  (b) failure by the Company
to comply with the terms of the Irrevocable Transfer Agent Instructions attached
to the  Securities  Purchase  Agreement;  (c) failure by the Company's  transfer
agent to issue Common Stock to the Holder  within ten (10) days of the Company's
receipt of the attached  Notice of  Conversion  from Holder;  (d) failure by the
Company  for ten (10) days  after  notice to it to comply  with any of its other
agreements  in the  Debenture;  (e) events of bankruptcy  or  insolvency;  (f) a
breach by the Company of its obligations under the Securities Purchase Agreement
or the Investor  Registration Rights Agreement which is not cured by the Company
within ten (10) days after receipt of written notice thereof.

         SECTION 3.02 FAILURE TO ISSUE  UNRESTRICTED  COMMON STOCK. As indicated
in Article III Section  3.01, a breach by the Company of its  obligations  under
the Investor  Registration Rights Agreement shall be deemed an Event of Default,
which if not cured within ten (10) days,  shall  entitle the Holder  accelerated
full  repayment of all debentures  outstanding.  The Company  acknowledges  that
failure to honor a Notice of  Conversion  shall  cause  irreparable  harm to the
Holder.

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                                   ARTICLE IV.

         SECTION 4.01 RIGHTS AND TERMS OF  CONVERSION.  Subject to Section 1.04,
this Debenture,  in whole or in part, may be converted at any time following the
date of closing,  into shares of Common Stock at a price equal to the Conversion
Price as described in Section 1.02 above.

         SECTION  4.02  RE-ISSUANCE  OF  DEBENTURE.  When the  Holder  elects to
convert a part of the Debenture,  then the Company shall reissue a new Debenture
in the same form as this Debenture to reflect the new principal amount.

         SECTION 4.03  TERMINATION OF CONVERSION  RIGHTS.  The Holder's right to
convert the Debenture  into the Common Stock in accordance  with  paragraph 4.01
shall terminate on the date that is the second (2nd) year  anniversary  from the
date hereof and this Debenture shall be automatically  converted on that date in
accordance  with  the  formula  set  forth  in  Section  4.01  hereof,  and  the
appropriate shares of Common Stock and amount of interest shall be issued to the
Holder.

         SECTION  4.04  RESTRICTION  ON SHORT SALE OF STOCK.  The Holder  hereby
acknowledges  and agrees that it shall not short sell the Common Stock except in
connection  with a  Conversion  Notice,  and  thereafter  only  such  number  of
Conversion Shares it receives with respect to such Conversion Notice.

                                   ARTICLE V.

         SECTION 5.01 ANTI-DILUTION.  In the event that the Company shall at any
time subdivide the  outstanding  shares of Common Stock,  or shall issue a stock
dividend  on the  outstanding  Common  Stock,  the  Conversion  Price in  effect
immediately  prior to such subdivision or the issuance of such dividend shall be
proportionately  decreased,  and in the event that the Company shall at any time
combine the outstanding  shares of Common Stock,  the Conversion Price in effect
immediately  prior  to such  combination  shall  be  proportionately  increased,
effective at the close of business on the date of such subdivision,  dividend or
combination as the case may be.

         SECTION 5.02 CONSENT OF HOLDER TO SELL  CAPITAL  STOCK.  Except for the
Equity Line of Credit  Agreement  dated the date hereof  between the Company and
Cornell Capital Partners,  LP. so long as any of the principal of or interest on
this Debenture  remains unpaid and  unconverted,  the Company shall not, without
the prior consent of the Holder, issue or sell (i) any Common Stock or Preferred
Stock without  consideration or for a consideration per share less than its fair
market value determined  immediately  prior to its issuance,  (ii) issue or sell
any Preferred Stock, warrant,  option, right, contract,  call, or other security
or  instrument  granting  the holder  thereof the right to acquire  Common Stock
without  consideration  or for a  consideration  per share less than such Common
Stock's fair market value determined  immediately  prior to its issuance,  (iii)
enter into any security  instrument  granting the holder a security  interest in
any and all assets of the  Company or (iv) file any  registration  statement  on
Form S-8.

                                   ARTICLE VI.

         SECTION 6.01 NOTICE.  Notices regarding this Debenture shall be sent to
the  parties  at the  following  addresses,  unless a party  notifies  the other
parties, in writing, of a change of address:

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If to the Company, to:              Vertical Computer Systems, Inc.
                                    6336 Wilshire Boulevard
                                    Los Angeles, CA 90048
                                    Attention:        Richard Wade
                                                      President
                                    Telephone:        (323) 658-4211
                                    Facsimile:        (322) 658-4214


With a copy to:                     Kirkpatrick & Lockhart LLP
                                    201 South Biscayne Boulevard - Suite 2000
                                    Miami, FL  33131-2399
                                    Attention:        Clayton E. Parker, Esq.
                                    Telephone:        (305) 539-3300
                                    Facsimile:        (305) 358-7095

If to the Holder:                   _______________________________

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

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

With a copy to:                     Butler Gonzalez LLP
                                    1000 Stuyvesant Avenue - Suite 6
                                    Union, NJ 07083
                                    Attention:        David Gonzalez, Esq.
                                    Telephone:        (908) 810-8588
                                    Facsimile:        (908) 810-0973

         SECTION 6.02 GOVERNING  LAW. This Debenture  shall be deemed to be made
under  and  shall be  construed  in  accordance  with  the laws of the  State of
Delaware  without  giving effect to the  principals of conflict of laws thereof.
Each of the parties  consents to the  jurisdiction  of the U.S.  District  Court
sitting in the  District  of the State of New Jersey or the state  courts of the
State of New Jersey sitting in Hudson County,  New Jersey in connection with any
dispute  arising under this Debenture and hereby  waives,  to the maximum extent
permitted by law, any  objection,  including  any  objection  based on FORUM NON
CONVENIENS to the bringing of any such proceeding in such jurisdictions.

         SECTION 6.03  SEVERABILITY.  The invalidity of any of the provisions of
this  Debenture  shall  not  invalidate  or  otherwise  affect  any of the other
provisions of this Debenture, which shall remain in full force and effect.

         SECTION 6.04 ENTIRE AGREEMENT AND AMENDMENTS. This Debenture represents
the entire  agreement  between  the parties  hereto with  respect to the subject
matter  hereof  and there are no  representations,  warranties  or  commitments,
except as set forth herein.  This Debenture may be amended only by an instrument
in writing executed by the parties hereto.

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         SECTION 6.05  COUNTERPARTS.  This Debenture may be executed in multiple
counterparts,  each of which  shall be an  original,  but all of which  shall be
deemed to constitute on instrument.

         IN WITNESS  WHEREOF,  with the intent to be legally bound  hereby,  the
Company as executed this Debenture as of the date first written above.

                                     VERTICAL COMPUTER SYSTEMS, INC.

                                       By:
                                     -------------------------------
                                     Name:    Richard S. Wade
                                     Title:   President


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                                   EXHIBIT "A"


                              NOTICE OF CONVERSION


           (TO BE EXECUTED BY THE HOLDER IN ORDER TO CONVERT THE NOTE)



TO:

         The undersigned hereby irrevocably elects to convert $ of the principal
amount of the above  Note into  Shares  of  Common  Stock of  Vertical  Computer
Systems,  Inc., according to the conditions stated therein, as of the Conversion
Date written below.


CONVERSION DATE:
                              -----------------------------------------------
APPLICABLE CONVERSION PRICE:
                              -----------------------------------------------
SIGNATURE:
                              -----------------------------------------------
NAME:
                              -----------------------------------------------
ADDRESS:
                              -----------------------------------------------
AMOUNT TO BE CONVERTED:  $
                              -----------------------------------------------
AMOUNT OF DEBENTURE UNCONVERTED: $
                              -----------------------------------------------
CONVERSION PRICE PER SHARE: $
                              -----------------------------------------------
NUMBER OF SHARES OF COMMON STOCK TO BE
                              -----------------------------------------------
ISSUED:
                              -----------------------------------------------
PLEASE ISSUE THE SHARES OF COMMON STOCK
IN THE FOLLOWING NAME AND TO THE
FOLLOWING ADDRESS:
                              -----------------------------------------------
ISSUE TO:
                              -----------------------------------------------
AUTHORIZED SIGNATURE:
                              -----------------------------------------------
NAME:
                              -----------------------------------------------
TITLE:
                              -----------------------------------------------
PHONE NUMBER:
                              -----------------------------------------------
BROKER DTC PARTICIPANT CODE:
                              -----------------------------------------------
ACCOUNT NUMBER:
                              -----------------------------------------------


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