EXHIBIT 4.1

                         VERTICAL COMPUTER SYSTEMS, INC.
                            (a Delaware Corporation)

                                STOCK OPTION PLAN

                                December 15, 1999

1. PURPOSE OF PLAN; ADMINISTRATION

1. Purpose

The Vertical Computer Systems, Inc. Stock Option Plan (hereinafter the "Plan"),
is hereby established to grant to officers and other employees of Vertical
Computer Systems, Inc., a Delaware corporation (the "Company") or its parents or
subsidiaries (as defined in Sections 424(e) and (f), respectively, of the
Internal Revenue Code of 1986, as amended (the "Code")), if any, and to
non-employee directors, consultants and advisors and other persons who may
perform significant services for or on behalf of the Company, a favorable
opportunity to acquire common stock, $.001 par value ("Common Stock"), of the
Company and, thereby, to create an incentive for such persons to remain in the
employ of or provide services to the Company and to contribute to its success.

The Company may grant under the Plan both incentive stock options within the
meaning of Section 422 of the Code ("Incentive Stock Options") and stock options
that do not qualify for treatment as Incentive Stock Options ("Nonstatutory
Options"). Unless expressly provided to the contrary herein, all references
herein to "options," shall include both incentive Stock Options and Nonstatutory
Options.

1.2 Administration

The Plan shall be administered by the Board of Directors of the Company (the
"Board" or "Committee"), or a committee of two or more directors. Appointment of
Committee members shall be effective upon acceptance of appointment. Committee
members may resign at any time by delivering written notice to the Board.
Vacancies in the Committee may be filled by the Board.

A majority of the members of the Committee shall constitute a quorum for the
purposes of the Plan. Provided a quorum is present, the Committee may take
action by affirmative vote or consent of a majority of its members present at a
meeting. Meetings may be held telephonically as long as all members are able to
hear one another, and a member of the Committee shall be deemed to be present
for this purpose if he or she is in simultaneous communication by telephone with
the other members who are able to hear one another. In lieu of action at a
meeting, the Committee may act by written consent of a majority of its members.

Subject to the express provisions of the Plan, the Committee shall have the
authority to construe and interpret the Plan and all Stock Option Agreements (as
defined in Section 3.4) entered into pursuant hereto and to define the terms
used therein, to prescribe, adopt, amend and rescind rules and regulations
relating to the administration of the Plan and to make all other determinations

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necessary or advisable for the administration of the Plan; provided, however,
that the Committee may delegate nondiscretionary administrative duties to such
employees of the Company as it deems proper; and, provided, further. in its
absolute discretion, the Board may at any time and from time to time exercise
any and all rights and duties of the Committee under the Plan. Subject to the
express limitations of the Plan, the Committee shall designate the individuals
from among the class of persons eligible to participate as provided in Section
1.3 who shall receive options, whether an optionee will receive Incentive Stock
Options or Nonstatutory Options, or both, and the amount, price, restrictions
and all other terms and provisions of such options (which need not be
identical).

Members of the Committee shall receive such compensation for their services as
members as may be determined by the Board. All expenses and liabilities which
members of the Committee incur in connection with the administration of this
Plan shall be borne by the Company. The Committee may, with the approval of the
Board, employ attorneys, consultants, accountants, appraisers, brokers or other
persons. The Committee, the Company and the Company's officers and directors
shall be entitled to rely upon the advice, opinions or valuations of any such
persons. No members of the Committee or the Board shall be personally liable for
any action, determination or interpretation made in good faith with respect to
the Plan, and all members of the Committee shall be fully protected by the
Company in respect of any such action, determination or interpretation.

1.3 Participation

Officers and other employees of the Company, non-employee directors, consultants
and advisors and other persons who may perform significant services on behalf of
the Company shall be eligible for selection to participate in the Plan upon
approval by the Committee; provided, however, that only "employees" (within the
meaning of Section 3401(c) of the Code) of the Company shall be eligible for the
grant of Incentive Stock Options. An individual who has been granted an option
may, if otherwise eligible, be granted additional options if the Committee shall
so determine. No person is eligible to participate in the Plan by matter of
right; only those eligible persons who are selected by the Committee in its
discretion shall participate in the Plan.

1.4 Stock Subject to the Plan.

Subject to adjustment as provided in Section 3.5, the stock to be offered tinder
the Plan shall be shares of authorized by unissued Common Stock, including any
shares repurchased under the terms of the Plan or any Stock Option Agreement
entered into pursuant hereto. The cumulative number of shares of Common Stock to
be issued under the Plan shall not exceed 2,500,000 subject to adjustment as set
forth in Section 3.5.

If any option granted hereunder shall expire or terminate for any reason without
having been fully exercised, the unpurchased shares subject thereto shall again
be available for the purposes of the Plan. For purposes of this Section 1.4,
where the exercise price of options is paid by means of the grantee's surrender
of previously owned shares of Common Stock, only the net number of additional
shares of Common Stock, only the net number of additional shares issued and
which remain

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outstanding in connection with such exercise shall be deemed "issued" for
purposes of the Plan.

2. STOCK OPTIONS

2.1 Exercise Price; Payment.

(a) The exercise price of each Incentive Stock Option granted under the Plan
shall be determined by the Committee, but shall not be less than 100% of the
"Fair Market Value" (as defined below) of Common Stock on the date of grant. If
an Incentive Stock Option is granted to an employee who at the time such option
is granted owns (within the meaning of section 424(d) of the Code) more than 10%
of the total combined voting power of all classes of capital stock of the
Company, the option exercise price shall be at least 110% of the Fair Market
Value of Common Stock on the date of grant. The exercise price of each
Nonstatutory Option also shall be determined by the Committee, but shall not be
less than 85% of the Fair Market Value of Common Stock on the date of grant. The
status of each option granted under the Plan as either an Incentive Stock Option
or a Nonstatutory Option shall be determined by the Committee at the time the
Committee acts to grant the option, and shall be clearly identified as such in
the Stock Option Agreement relating thereto.

"Fair Market Value" for purposes of the Plan shall mean: (i) the closing price
of a share of Common Stock on the principal exchange on which shares of Common
Stock are then trading, if any, on the day immediately preceding the date of
grant, or, if shares were not traded on the day preceding such date of grant,
then on the next preceding trading day during which a sale occurred; or (ii) if
Common Stock is not traded on as exchange but is quoted on NASDAQ or a successor
quotation system, (1) the last sales price (if Common Stock is then listed on
the NASDAQ Stock Market) or (2) the mean between the closing representative bid
and asked price (in all other cases) for Common Stock on the day prior to the
date of grant as reported by NASDAQ or such successor quotation system or (iii)
if there is no listing or trading of Common Stock either on a national exchange
or over-the-counter, that price determined in good faith by the Committee to be
the fair value per share of Common Stock, based upon such evidence as it deems
necessary or advisable.

(b) In the discretion of the Committee at the time the option is exercised, the
exercise price of any option granted under the Plan shall be paid in full in
cash, by check or by the optionee's interest-bearing promissory note (subject to
any limitations of applicable state corporations law) delivered at the time of
exercise; provided, however, that subject to the timing requirements of Section
2.7, in the discretion of the Committee and upon receipt of all regulatory
approvals, the person exercising the option may deliver as payment in whole or
in part of such exercise price certificates for Common Stock of the Company
(duly endorsed or with duly endorsed stock powers attached), which shall be
valued at its Fair Market Value on the day of exercise of the option, or other
property deemed appropriate by the Committee; and, provided further, that
subject to Section 422 of the Code, so-called cashless exercises as permitted
under applicable rules and regulations of the Securities and Exchange Commission
and the Federal Reserve Board shall be permitted in the discretion of the
Committee. Without limiting the Committee's discretion in this regard,
consecutive

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book entry stock-for-stock exercises of options (or "pyramiding") also are
permitted in the Committee's discretion.

Irrespective of the form of payment, the delivery of shares issuable upon the
exercise of an option shall be conditioned upon payment by the optionee to the
Company of amounts sufficient to enable the Company to pay all federal, state,
and local withholding taxes resulting in, the Company's judgment, from the
exercise. In the discretion of the Committee, such payment to the Company may be
effected through (i) the Company's withholding from the number of shares of
Common Stock that would otherwise be delivered to the optionee by the Company on
exercise of the option a number of shares of Common Stock equal in value (as
determined by the Fair Market Value of Common Stock on the date of the exercise)
to the aggregate withholding taxes, (ii) payment by the optionee to the Company
of the aggregate withholding taxes in cash, (iii) withholding by the Company
from other amounts contemporaneously owed by the Company to the optionee, or
(iv) any combination of these three methods, as determined by the Committee in
its discretion.

2.2 Option Period.

(a) The Committee shall provide, in the terms of each Stock Option Agreement,
when the option subject to such agreement expires and becomes unexercisable, but
in no event will an Incentive Stock Option granted under the Plan be exercisable
after the expiration often years from the date is granted. Without limiting the
generality of the foregoing, the Committee may provide in the Stock Option
Agreement that the option subject thereto expires 30 days following a
Termination of Employment (as defined in Section 3.2 hereof) for any reason
other than death or disability, or six months following a Termination of
Employment for disability or following an optionee's death.

(b) Outside Date for Exercise. Notwithstanding any provisions of this Section
2.2, in no event shall any option granted under the Plan be exercised after the
expiration date of such option set forth in the applicable Stock Option
Agreement.

2.3 Exercise of Options.

Each option granted under the Plan shall become exercisable and the total number
of shares subject thereto shall be purchasable, in a lump sum or in such
installments, which need not be equal, as the Committee shall determine;
provided, however, that each option shall become exercisable in full no later
than ten years after such option is granted, and each option shall become
exercisable as to at least 10% of the shares of Common Stock covered thereby on
each anniversary of the date such option is granted; and provided, further, that
if the holder of an option shall not in any given installment period purchase
all of the shares which such holder is entitled to purchase in such installment
period, such holder's right to purchase any share not purchased in such
installment period shall continue until the expiration or sooner termination of
such holder's option. The Committee may, at any time after grant of the option
and from time to time, increase the number of shares purchasable in any
installment, subject to the total number of shares subject to the option and the
limitations set forth in Section 2.5. At any time and from time to time prior to
the time when any exercisable option or exercisable portion thereof becomes
unexercisable under the Plan or the applicable Stock Option Agreement, such
option, or portion thereof may be exercised in whole or in part; provided,
however, that the Committee may, by the terms of the option, require any partial
exercise to be with respect to a specified minimum number of shares. No option
or installment thereof shall be exercisable except with respect to whole shares.
Fractional share interests shall be disregarded, except that they may be
accumulated as provided above and except that if such a fractional share
interest constitutes the total the total shares of Common Stock remaining
available for purchase under an option at the time of exercise, the optionee
shall be entitled to receive on exercise a certified or bank cashier's check in
an amount equal to the Fair Market Value of such fractional share of stock.

      2.4 Transferability of Options.

Except as the Committee may determine as aforesaid, an option granted under the
Plan shall, by its terms, be nontransferable by the optionee other than by will
or the laws of descent and distribution, or pursuant to a qualified domestic
relations order (as defined by the Code), and shall be exercisable during the
optionee's lifetime only by the optionee or by his or her guardian or legal
representative. More particularly, but without limiting the generality of the
immediately preceding sentence, an option may not be assigned, transferred

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(except as provided in the preceding sentence), pledged or hypothecated (whether
by operation of law or otherwise), and shall not be subject to execution,
attachment or similar process. Any attempted assignment, transfer, pledge,
hypothecation or other disposition of any option contrary to the provisions of
the Plan and the applicable Stock Option Agreement, and any levy of any
attachment or similar process upon an option, shall be null and void, and
otherwise without effect, and the Committee may, in its sole discretion, upon
the happening of any such event, terminate such option forthwith.

2.5 Limitation on Exercise of Incentive Stock Options.

To the extent that the aggregate Fair Market Value (determined on the date of
grant as provided in Section 2.1 above) of the Common Stock with respect to
which Incentive Stock Options granted hereunder (together with all other
Incentive Stock Option plans of the Company) are exercisable for the first time
by an optionee in any calendar year under the Plan exceeds $100,000, such
options granted hereunder shall be treated as Nonstatutory Options to the extent
required by Section 422 of the Code. The rule set forth in the preceding
sentence shall be applied by taking options into account in the order in which
they were granted.

2.6 Disqualifying Dispositions of Incentive Stock Options.

If Common Stock acquired upon exercise of any Incentive Stock Option is disposed
of in a disposition that, under Section 422 of the Code, disqualifies the option
holder from the application of Section 42 1(a) of the Code, the holder of the
Common Stock immediately before the disposition shall comply with any
requirements imposed by the Company in order to enable the Company to secure the
related income tax deduction to which it is entitled in such event.

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2.7 Certain Timing Requirements.

At the discretion of the Committee, shares of Common Stock issuable to the
optionee upon exercise of an option may be used to satisfy the option exercise
price or the tax withholding consequences of such exercise, in the case of
persons subject to Section 16 of the Securities Exchange Act of 1934, as
amended, only (i) during the period beginning on the third business day
following the date of release of the quarterly or annual summary statement of
sales and earnings of the company and ending on the twelfth business day
following such date or (ii) pursuant to an irrevocable written election by the
optionee to use shares of Common Stock issuable to the optionee upon exercise of
the option to pay all or part of the option price or the withholding taxes made
at least six months prior to the payment of such option price or the withholding
taxes made at least six months prior to the payment of such option price or
withholding taxes.

2.8 No Effect on Employment.

Nothing in the Plan or in any Stock Option Agreement hereunder shall confer upon
any optionee any right to continue in the employ of the Company, any Parent
Corporate or any subsidiary or shall interfere with or restrict in any way the
rights of the Company, its Parent Corporation and its Subsidiaries, which are
hereby expressly reserved, to discharge any optionee at any time for any reason
whatsoever, with or without cause.

For purposes of the Plan, "Parent Corporation" shall mean any corporation in an
unbroken chain of corporations ending with the Company if each of the
corporations other than the Company then owns stock possessing 50% or more of
the total combined voting power of all classes of stock in one of the other
corporations in such chain. For purposes of the Plan, "Subsidiary" shall mean
any corporation in an unbroken chain of corporations beginning with the Company
if each of the corporations other than the last corporation in the unbroken
chain then owns stock possessing 50% or more of the total combined voting power
of all classes of stock in one of the other corporations in such chain.

3. OTHER PROVISIONS

3.1 Sick Leave and Leaves of Absence

Unless otherwise provided in the Stock Option Agreement, and to the extent
permitted by Section 422 of the Code, an optionee's employment shall not be
deemed to terminate by reason of sick leave, military leave or other leave of
absence approved by the Company if the period of any such leave does not exceed
a period approved by the Company is guaranteed either contractually or by
statute. A Stock Option Agreement may contain such additional or different
provisions with respect to leave of absence as the Committee may approve, either
at the time of grant of an option or at a later time.

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3.2 Termination of Employment.

For purposes of the Plan "Termination of Employment," shall mean the time when
the employee-employer relationship between the optionee and the Company, any
Subsidiary or any Parent Corporation is terminated for any reason, including,
but not by way of limitation, a termination by resignation, discharge, death,
disability or retirement; but excluding (i) terminations where there is a
simultaneous reemployment or continuing employment of an optionee by the
Company, any Subsidiary or any Parent Corporation, (ii) at the discretion of the
Committee, terminations which result in a temporary severance of the
employee-employer relationship, and (iii) at the discretion of the committee,
terminations which are followed by the simultaneous establishment of a
consulting relationship by the Company, a Subsidiary or any Parent Corporation
with the former employee. Subject to Section 3.1, the Committee, in its absolute
discretion, shall determine the effect of all matters and questions relating to
Termination of Employment; provided, however, that, with respect to
employee-employer relationship shall constitute a Termination of Employment if
and to the extent that such leave of absence or other change interrupts
employment for the purposes of Section 422(a) (2) of the Code and the
then-applicable regulations and revenue ruling under said Section.

3.3 Issuance of Stock Certificates.

Upon exercise of an option, the Company shall deliver to the person exercising
such option a stock certificate evidencing the shares of Common Stock acquired
upon exercise. Notwithstanding the foregoing, the Committee in its discretion
may require the Company to retain possession of any certificate evidencing stock
acquired upon exercise of an option which remains subject to repurchase under
the provisions of the Stock Option Agreement or any other agreement signed by
the optionee in order to facilitate such repurchase provisions.

3.4 Terms and Conditions of Options.

Each option granted under the Plan shall be evidenced by a written Stock Option
Agreement ("Stock Option Agreement") between the option holder and the Company
providing that the option is subject to the terms and conditions of the Plan and
to such other terms and conditions not inconsistent therewith as the Committee
may deem appropriate in each case.

3.5 Adjustments Upon Changes in Capitalization; Merger and Consolidation.

If the outstanding share of Common Stock are changed into, or exchanged for cash
or a different number or kind of shares or securities of the Company or of
another corporation through reorganization, merger, recapitalization,
reclassification, stock split-up, reverse stock split, stock dividend, stock
consolidation, stock combination, stock reclassification or similar transaction,
an appropriate adjustment shall be made by the Committee in the number and kind
of shares as to which options may be granted. In the event of such a change or
exchange, other than for shares or securities of another corporation or by
reason of reorganization, the Committee shall also make a corresponding
adjustment changing the number or kind of shares and the exercise price per
share allocated to unexercised options or portions thereof; which shall have
been granted prior to any such change, shall likewise be made. Any such
adjustment, however, shall be made without change in the total price applicable
to the unexercised portion of the option (except for any change in the aggregate
price resulting from rounding-off of shares quantities or prices).

In the event of a "spin-off' or other substantial distribution of assets of the
Company which has a material diminutive effect upon the Fair Market Value of the
Common Stock, the Committee in its discretion shall make an appropriate and
equitable adjustment to the exercise prices of options then outstanding under
the Plan.

Where an adjustment under this Section 3.5 of the type described above is made
to an Incentive Stock Option, the adjustment will be made in a manner which will
not be considered a "modification" under the provisions of subsection 424(b)(3)
of the Code.

In connection with the dissolution or liquidation of the Company or a partial
liquidation involving 50% or more of the assets of the Company, a reorganization
of the Company in which another entity is the survivor, a merger or
reorganization of the Company under which more than 50% of the Common Stock
outstanding prior to the merger or reorganization is converted into cash or into
a security of another entity, a sale of more than 50% of the Company's assets,
or a similar event that the Committee determines, in its discretion, would

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materially alter the structure of the Company or its ownership, the Committee,
upon 30 days prior written notice to the option holders, may, in its discretion,
do one or more of the following: (i) shorten the period during which options are
exercisable (provided they remain exercisable for at least 30 days after the
date the notice is given); (ii) accelerate any vesting schedule to which an
option is subject; (iii) arrange to have the surviving or successor entity grant
securities and option prices, or (iv) cancel options upon payment to the option
holders in cash, with respect to each option to the extent then exercisable
(including any options as to which the exercise has been accelerated as
contemplated in clause (ii) above, of any amount that is the equivalent of the
Fair Market Value of the Common Stock (at the effective time of the dissolution,
liquidation, merger, reorganization, sale or other event) or the fair market
value of the option. In the case of a change in corporate control, the Committee
acceleration of the exercisability of any option pursuant to this Section 3.5,
take into account the penalties that my result directly or indirectly from such
acceleration to either the Company or the option holder, or both, under Section
280G of the Code, and may decide to limit such acceleration to the extent
necessary to avoid or mitigate such penalties or their effects.

No fractional share of Common Stock shall be issued under the Plan on account of
any adjustment under this Section 3,5.

3.6 Rights of Participants and Beneficiaries.

The Company shall pay all amounts payable hereunder only to the option holder or
beneficiaries entitled thereto pursuant to the Plan. The Company shall not be
liable for the date,

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3.10 Privileges of Stock Ownership; Non-Distributive Intent; Reports to Option
Holders. A participant in the Plan shall not be entitled to the privilege of
stock ownership as to any shares of Common Stock not actually issued to the
optionee. Upon exercise of an option at a time when there is not in effect under
the Securities Act of 1933, as amended, a Registration Statement relating to the
delivery a Prospectus meeting the requirement of Section 1 O(a)(3) of said Act,
the optionee shall represent and warrant in writing to the Company that the
shares purchased are being acquired for investment and not with a view to the
distribution thereof.

The Company shall furnish to each optionee under the Plan the Company's annual
report and such other periodic reports, if any, as are disseminated by the
Company in the ordinary course to its stockholders.

3.11 Legending Share Certificates.

In order the enforce any restrictions imposed upon Common Stock issued upon
exercise of an option granted under the Plan or to which such Common Stock may
be subject, the Committee may cause a legend or legends to be placed on any
share certificates representing such Common Stock, which legend or legends shall
made appropriate reference to such restrictions, including, but not limited to,
a restriction against sale of such Common Stock for any period of time as may be
required by applicable laws or regulations. If any restrictions with respect to
which a legend was placed on any certificate ceases to apply to Common Stock
represented by such certificate, the owner of the Common Stock represented by
such certificates may require the Company to cause the issuance of a new
certificate not bearing the legend.

Additionally, and not by way of limitation, the Committee may impose such
restrictions on any Common Stock issued pursuant to the Plan as it may deem
advisable, including, without limitation., restrictions under the requirements
of any stock exchange upon which Common Stock is then traded.

3.12 Use of Proceeds.

Proceeds realized pursuant to the exercise of options Under the Plan shall
constitute general funds of the Company.

3.13 Changes in Capital Structure; No Impediment to Corporate Transaction.

The existence of outstanding options under the Plan shall not effect the
Company's right to effect adjustments, recapitalization, reorganizations or
other changes in its or any other corporation's capital structure or business,
any merger or consolidation, any issuance of bonds, debentures, preferred or
prior preference stock ahead of or affecting Common Stock, the dissolution or
liquidation of the Company's or any other corporation's assets or business, or
any other corporate act, whether similar to the events described above or
otherwise.

3.14 Effective Date of the Plan.

The Plan shall be effective as of the date of its approval by the stockholders
of the Company within twelve months after the date of the Board's initial
adoption of the Plan. Options may be granted but not exercised prior to
stockholder approval of the Plan. If any options are so granted and stockholder
approval shall not have been obtained within twelve months of the date of
adoption of this Plan by the Board of Directors, such options shall terminate
retroactively as of the date they were granted.

3.15 Termination.

The Plan shall terminate automatically as of the close of business on December
15, 2009 or earlier as provided in Section 3.8. Unless otherwise provided
herein, the termination of the Plan shall not affect the validity of any option
agreement outstanding at the date of such termination.

3.16 No Effect on Other Plans.

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The adoption of the Plan shall not affect any other compensation or incentive
plans in effect for the Company, any Subsidiary or any Parent Corporation.
Nothing in the Plan shall be construed to limit the right of the Company (i) to
establish any other forms or incentives or compensation for employees of the
Company, any Subsidiary or any Parent Corporation or (ii) to grant or assume
options or other rights otherwise that under the Plan in connection with any
proper corporate purpose including but not by way of limitation, the grant or
assumption of options in connection with the acquisition by purchase, lease,
merger, consolidation or otherwise, of the business, stock or assets of any
corporation, partnership, firm or association.