<PAGE>

                                                                     Exhibit 4.1

THE DATAVON INC. 2000 STOCK OPTION PLAN HAS BEEN ASSUMED BY ZYDECO ENERGY, INC.
PURSUANT TO THE AGREEMENT AND PLAN OF MERGER, DATED MAY 23, 2000, BY AND AMONG
ZYDECO, DATAVON INC., AND DVN ACQUISITION CORPORATION.

                                 DATAVON INC.

                            2000 STOCK OPTION PLAN
                            ----------------------


     1.   PURPOSE.
          -------

          DataVoN Inc. 2000 Stock Option Plan (the "Plan") is intended to
provide to officers, directors, key employees and consultants of DataVoN Inc., a
Texas corporation (the "Corporation"), an opportunity to acquire a proprietary
interest in the Corporation, to encourage such key individuals to remain in the
employ of or to contract with the Corporation, and to attract and retain new
employees, consultants, and directors with outstanding qualifications.  Pursuant
to the Plan, the Corporation may grant to officers, directors, consultants, and
key employees of the Corporation options to purchase shares of common stock of
the Corporation upon such terms and conditions as provided herein.


     2.   DEFINITIONS.
          -----------

          (a)  "Affiliate" shall mean any corporation (other than the
                ---------
Corporation) in an unbroken chain of corporations that includes the Corporation
if each of such corporations, other than the last corporation in the chain, owns
at least 50% of the total voting power of one of the other corporations.

          (b)  "Award" shall mean a grant of an Option, an SAR, and/or
                -----
Restricted Stock under the Plan.

          (c)  "Board" shall mean the Board of Directors of the Corporation.
                -----

          (d)  "Code" shall mean the Internal Revenue Code of 1986, as amended.
                ----

          (e)  "Committee" shall mean the committee appointed by the Board to
                ---------
administer the Plan, or if no such committee is appointed, the Board.

          (f)  "Common Stock" shall mean the voting common stock of the
                ------------
Corporation.

                                       1
<PAGE>

          (g)  "Consultant" shall mean any person who, or any employee of any
                ----------
firm which, is engaged by the Corporation or any Affiliate to render consulting
services and is compensated for such consulting services, and any non-employee
director of the Corporation whether compensated for such services or not.

          (h)  "Corporation" shall mean DataVoN Inc., a Texas corporation.
                -----------

          (i)  "Effective Date" shall mean March 17, 2000.
                --------------

          (j)  "Employee" shall mean any individual who is employed, within the
                --------
meaning of Section 3401 of the Code and the regulations thereunder, by the
Corporation or by any Affiliate. For purposes of the Plan and only for purposes
of the Plan, and in regard to Nonstatutory Stock Options but not for Incentive
Stock Options, a Consultant or director of the Corporation or any Affiliate
shall be deemed to be an Employee, and service as a Consultant or director with
the Corporation or any Affiliate shall be deemed to be employment, but no
Incentive Stock Option shall be granted to a Consultant or director who is not
an employee of the Corporation or any Affiliate within the meaning of Section
3401 of the Code and the regulations thereunder. In the case of a non-employee
director or Consultant, the provisions governing when a termination of
employment has occurred for purposes of the Plan shall be set forth in the
written stock option agreement between the Optionee and the Corporation, or, if
not so set forth, the Committee shall have the discretion to determine when a
termination of "employment" has occurred for purposes of the Plan.

          (k)  "Escrow Agent" shall mean the person selected by the Corporation,
                ------------
if any, to hold the stock certificates representing Shares issued in the name of
an Optionee pursuant to such Optionee's exercise of an Option.

          (l)  "Exchange Act" shall mean the Securities Exchange Act of 1934, as
                ------------
amended.

          (m)  "Exercise Price" shall mean the price per Share at which an
                --------------
Option may be exercised, as determined by the Committee and as specified in
the Optionee's stock option agreement.

          (n)  "Fair Market Value" shall mean the value of each Share as
                -----------------
determined by the Board; provided, however, that if there is a public market for
                         --------  -------
the securities, the Fair Market Value shall be the mean of the bid and asked
prices of the securities per share or unit, as the case may be, as reported in
the Wall Street Journal (or, if not so reported, as otherwise reported by the
National Association of Securities Dealers Automated Quotation System) as of the
date in question or, in the event the securities are listed on a stock exchange,
the Fair Market Value shall be the closing sales price of the securities per
share or unit, as the case may be, on such exchange, as reported in the Wall
Street Journal, as of the date in question.

                                       2
<PAGE>

          (o)  "Incentive Stock Option" shall mean an Option of the type
                ----------------------
described in Section 422(b) of the Code.

          (p)  "Joint Escrow Instructions" shall mean joint escrow instructions
                -------------------------
entered into between Optionee and the Corporation in such form as may be
approved by the Committee from time to time.

          (q)  "Nonstatutory Stock Option" shall mean an Option of the type not
                -------------------------
described in Section 422(b) or 423(b) of the Code.

          (r)  "Option" shall mean an option to purchase Common Stock granted
                ------
pursuant to the Plan.

          (s)  "Optionee" shall mean any person who holds an Option pursuant to
                --------
the Plan.

          (t)  "Plan" shall mean this stock option plan as it may be amended
                ----
from time to time.

          (u)  "Purchase Price" shall mean at any particular time the Exercise
                --------------
Price times the number of Shares for which an Option is being exercised.

          (v)  "Restricted Stock" shall mean an Award pursuant to which eligible
                ----------------
Employees selected by the Committee in its sole discretion receives Shares
issued to such Employees with such restrictions on transfer as the Committee in
its sole discretion shall determine from time to time and the stock certificates
evidencing such Shares shall bear legends of such restrictions on transfer.

          (w)  "SAR" shall mean stock appreciation rights, an Award pursuant to
                ---
which eligible Employees selected by the Committee in its sole discretion
receives a right to a cash settlement payment upon exercise equal to the excess
of the Fair Market Value of one share of Common Stock on the date of exercise
over the Fair Market Value of one share of Common Stock on the grant date of the
SAR, multiplied by the number of SARs granted.

          (x)  "Share" shall mean share of the authorized Common Stock.
                -----

          (y)  "Subsidiary" shall mean any corporation as to which more than
                ----------
fifty (50%) percent of the outstanding voting stock or shares shall now or
hereafter be owned or controlled, directly by a person, any Subsidiary of such
person, or any Subsidiary of such Subsidiary.


     3.   ADMINISTRATION.
          --------------

          (a)  The Committee.
               -------------

                                       3
<PAGE>

               (i)   The Board may administer the Plan or appoint a Committee to
administer the Plan. The Committee shall consist of not less than two members
who may also be members of the Board. Members of the Board or the Committee who
are either eligible for Awards or have been granted Awards may vote on any
matters affecting the administration of the Plan or the grant of any Awards
pursuant to the Plan, except that no such member shall act upon the granting of
an Award to himself or herself, but any such member may be counted in
determining the existence of a quorum at any meeting of the Committee and shall
be excluded in determining unanimity of an act in writing, for any action which
is taken with respect to the granting of an Award to such member.

               (ii)  If the Corporation registers any class of any equity
security pursuant to Section 12 of the Exchange Act from the effective date of
such registration until six months after the termination of such registration,
the Plan shall be administered by a Committee of directors which shall consist
of not less than two members, who during the one year prior to service as an
administrator of the Plan, shall not have been granted or awarded equity
securities pursuant to the Plan or any other plan of the Corporation or any of
its Affiliates except as permitted under Rule 16b-3 under the Exchange Act which
provides that participation in a formula plan meeting the conditions of Rule
16(b)(3)(c)(2)(ii) or in an ongoing securities acquisition plan meeting the
conditions in Rule 16(b)(3)(d)(2)(i) shall not disqualify a member of the
Committee from serving as an administrator of the Plan. In addition, an election
to receive an annual retainer fee in either cash or an equivalent amount of
securities, or partly in cash and partly in securities, shall not disqualify a
member of the Committee from serving as an administrator of the Plan.

          The Board may from time to time designate individuals as ineligible to
participate in the Plan for a specified period in order to become eligible to be
a member of the Committee.

          (b)  Powers of the Committee.
               -----------------------

          Subject to the provisions of the Plan, the Committee shall have the
authority, in its discretion and on behalf of the Corporation:

               (i)    to grant Options;

               (ii)   to determine the Exercise Price per Share of Options to be
granted;

               (iii)  to determine the Employees to whom, and the time or times
at which, Options shall be granted and the number of Shares for which an Option
will be exercisable;

               (iv)   to interpret the Plan;

                                       4
<PAGE>

               (v)     to prescribe, amend, and rescind rules and regulations
relating to the Plan;

               (vi)    to determine the terms and provisions of each Option
granted and, with the consent of the holder thereof, modify or amend each
Option;

               (vii)   to accelerate or defer, with the consent of the
Optionee, the exercise date of any Option;

               (viii)  with the consent of the Optionee, to reprice, cancel and
regrant, or otherwise adjust the Exercise Price of an Option or other Awards
previously granted by the Committee;

               (ix)    to grant SARs and/or Restricted Stocks, and determine the
terms and conditions of such Awards and the forms of the instruments necessary
or advisable in the administration of the Awards;

               (x)     to authorize any person to execute on behalf of the
Corporation any instrument required to effectuate the grant of an Award
previously granted by the Committee; and

               (xi)    to make all other determinations deemed necessary or
advisable for the administration of the Plan.

          (c)  Board's Determination of Fair Market Value.
               ------------------------------------------

               The Board shall have the authority to determine, upon review of
relevant information, the Fair Market Value of the Common Stock, subject to the
provisions of the Plan and irrespective of whether the Board has appointed a
Committee to administer the Plan.  The Board may delegate this authority to the
Committee.

          (d)  Committee's Interpretation of the Plan.
               --------------------------------------

               The interpretation and construction by the Committee of any
provision of the Plan or of any Award granted hereunder shall be final and
binding on all parties claiming an interest in an Award granted under the Plan.
No member of the Committee shall be liable for any action or determination made
in good faith with respect to the Plan or any Award.

          (e)  All Committee Actions to be in Writing.
               --------------------------------------

               Any and all actions of the Committee taken in exercise of the
powers granted to it in this Section 3 shall be in writing.

                                       5
<PAGE>

          (f)  Delegation by Committee
               -----------------------

               Subject to the provisions of the Plan, the Committee shall have
the authority, in its discretion and on behalf of the Corporation, to delegate
the following powers to any individual or individuals with respect to the
granting of Options to those Employees who are not subject to the short-swing
profit rules of Section 16 of the Exchange Act:

               (i)   The power to grant Options;

               (ii)  The power to determine the Employees to whom and the time
or times at which Options shall be granted and the number of Shares for which an
Option will be exercisable; and

               (iii) The power to determine the Exercise Price per Share of
Options to be granted.

               In delegating its powers hereunder, the Committee may place any
restrictions it deems appropriate on the delegatee(s).  Any delegation of power
under this Section shall be valid until it expires by its own terms, until
revoked by the Committee, or until revoked by the Board, whichever first occurs.


     4.   PARTICIPATION.
          -------------

          (a)  Eligibility.
               -----------

               The Optionees shall be such persons as the Committee may select
from among the Employees, provided that Consultants and directors who are not an
employee of the Corporation are not eligible to receive Incentive Stock Options.

          (b)  Ten Percent (10%) Shareholders.
               ------------------------------

               Any Employee who owns stock possessing more than ten percent
(10%) of the total combined voting power of all classes of outstanding stock of
the Corporation or any Affiliate shall not be eligible to receive an Option
unless:

               (i)   the Exercise Price of the Shares subject to such Option
when granted is at least one hundred and ten percent (110%) of the Fair Market
Value of such Shares, and

               (ii)  such Option by its terms is not exercisable after the
expiration of five (5) years from the date of grant.

          (c)  Stock Ownership.
               ---------------

                                       6
<PAGE>

               For purposes of Section 4(b), in determining stock ownership, an
Employee shall be considered as owning the stock owned, directly or indirectly,
by or for his or her brothers and sisters, spouse, ancestors, and lineal
descendants.  Stock owned, directly or indirectly, by or for a corporation,
partnership, estate, or trust shall be considered as being owned proportionately
by or for its shareholders, partners, or beneficiaries, respectively.  Stock
with respect to which such Employee or any other person holds an option shall be
disregarded.

          (d)  Outstanding Stock.
               -----------------

               For purposes of Section 4(b), the term "outstanding stock" shall
mean and include all stock of the Corporation actually issued and outstanding
immediately after the grant of the Option to the Optionee but shall not include
any Share for which an Option is exercisable by any person.


     5.   SHARES SUBJECT TO THE PLAN.
          --------------------------

          (a)  Shares Subject to The Plan.
               --------------------------

               The aggregate number of Shares which may be issued upon exercise
of Options under the Plan shall not exceed 100,000 subject to adjustment
pursuant to Section 9 hereof.

          (b)  Options Not to Exceed Shares Available.
               --------------------------------------

               The number of Shares for which an Option is exercisable at any
time shall not exceed the number of Shares remaining available for issuance
under the Plan. If any Option expires or is terminated, the number of Shares for
which such Option was exercisable may be made exercisable pursuant to other
Options under the Plan. If the Corporation reacquires any Shares pursuant to
Sections 11 or 12, hereof, such Shares may again be made exercisable pursuant to
an Option. The limitations established by this Section 5(b) shall be subject to
adjustment in the manner provided in Section 9 hereof upon the occurrence of an
event specified therein.

     6.   TERMS AND CONDITIONS OF OPTIONS.
          -------------------------------

          (a)  Stock Option Agreements.
               -----------------------

               Options shall be evidenced by written stock option agreements
between the Optionee and the Corporation in the form attached hereto as Exhibit
A for Nonstatutory Stock Options and in the form attached hereto as Exhibit B
for Incentive Stock Options, incorporated herein by reference, or in such other
forms or modified forms as the Committee shall hereafter from time to time
determine. No Option or

                                       7
<PAGE>

purported Option shall be a valid and binding obligation of the Corporation
unless so evidenced in writing.

          (b)  Number of Shares.
               ----------------

               Each stock option agreement shall state the number of Shares for
which the Option is exercisable and shall provide for the adjustment thereof in
accordance with Section 9 hereof.

          (c)  Vesting.
               -------

               An Optionee may not exercise his or her Option for any Shares
until the Option, in regard to such Shares, has vested. Each stock option
agreement shall include a vesting schedule determined in the discretion of the
Committee, which shall show when the Option becomes exercisable provided, each
Option shall vest at a rate of at least twenty percent (20%) per year over a
period of five (5) years. The vesting schedule shall not impose upon the
Corporation or any Affiliate any obligation to retain the Optionee in its employ
or under contract for any period or otherwise change the employment-at-will
status of an Optionee who is an employee of the Corporation or any Affiliate.

          (d)  Lapse of Options.
               ----------------

               Each stock option agreement shall state the time or times when
the Option covered thereby lapses and becomes unexercisable in part or in full.
An Option shall lapse on the earliest of the following events (unless otherwise
determined by the Committee and reflected in an option agreement):

               (i)   The tenth anniversary of the date of granting the Option;

               (ii)  The first anniversary of the Optionee's death;

               (iii) The first anniversary of the date the Optionee ceases to
be an Employee due to total and permanent disability;

               (iv)  On the date provided in Section 6(h)(i), unless with
respect to a Nonstatutory Stock Option, the Committee otherwise extends such
period before the applicable expiration date;

               (v)   On the date provided in Section 9 for a transaction
described in Section 9;

               (vi)  The date the Optionee files or has filed against him or
her a petition in bankruptcy; or

                                       8
<PAGE>

               (vii) The expiration date specified in an Optionee's stock
option agreement.

          (e)  Exercise Price.
               --------------

               Each stock option agreement shall state the Exercise Price for
the Shares for which the Option is exercisable. Subject to Section 4(b), the
Exercise Price of an Incentive Stock Option and a Nonstatutory Stock Option
shall, when granted, be not less than one hundred percent (100%) and eighty-five
percent (85%) of the Fair Market Value of the Shares for which the Option is
exercisable, respectively, and not less than the par value of the Shares.

          (f)  Medium and Time of Payment.
               --------------------------

               The Purchase Price shall be payable in full in cash upon the
exercise of an Option but the Committee may allow the Optionee to pay the
Purchase Price:

               (i)   by surrendering Shares in good form for transfer, owned by
the Optionee and having a Fair Market Value on the date of exercise equal to the
Purchase Price;

               (ii)  by delivery of a full recourse promissory note (the "Note")
made by the Optionee in the amount of the Purchase Price, bearing interest,
compounded semi-annually, at a rate not less than the rate determined under
Section 7872 of the Code to insure that no "foregone interest", as defined in
such section, will accrue, together with the delivery of a duly executed
standard form security agreement securing the Note by a pledge of the Shares
purchased; or

               (iii) in any combination of such consideration or such other
consideration and method of payment for the issuance of Shares to the extent
permitted under applicable law as long as the sum of the cash so paid, the Fair
Market Value of the Shares so surrendered, and the amount of any Note equals the
Purchase Price.

               The Committee or a stock option agreement may prescribe
requirements with respect to the exercise of Options, including the submission
by the Optionee of such forms and documents as the Committee may require and,
the delivery by the Optionee of cash sufficient to satisfy applicable
withholding requirements. The Committee may vary the exercise requirements and
procedures from time to time to facilitate, for example, the broker-assisted
exercise of Options.

          (g)  Nontransferability of Options.
               -----------------------------

               During the lifetime of the Optionee, the Option shall be
exercisable only by the Optionee or the Optionee's conservator or legal
representative and shall not

                                       9
<PAGE>

be assignable or transferable. In the event of the Optionee's death, the Option
shall not be transferable by the Optionee other than by will or the laws of
descent and distribution.

          (h)  Termination of Employment other than by Death or Disability.
               -----------------------------------------------------------

               (i)   If an Optionee ceases to be an Employee for any reason
other than his or her death or disability, the Optionee shall have the right,
subject to the provisions of this Section 6, to exercise any Option held by the
Optionee at any time within thirty (30) days after his or her termination of
employment, but not beyond the otherwise applicable term of the Option and only
to the extent that on such date of termination of employment the Optionee's
right to exercise such Option had vested.

               (ii)  For purposes of this Section 6(h), the employment
relationship shall be treated as continuing intact while the Optionee is an
active employee of the Corporation or any Affiliate, or is on military leave,
sick leave, or other bona fide leave of absence to be determined and approved in
writing in the sole discretion of the Committee. The preceding sentence
notwithstanding, in the case of an Incentive Stock Option, employment shall be
deemed to terminate on the date the Optionee ceases active employment with the
Corporation or any Affiliate, unless the Optionee's reemployment rights are
guaranteed by statute or contract.

          (i)  Death of Optionee.
               -----------------

               If an Optionee dies while an Employee, or after ceasing to be an
Employee but during the period while he or she could have exercised an Option
under Section 6(h), any Option granted to the Optionee may be exercised, to the
extent it had vested at the time of death and subject to the Plan, at any time
within twelve (12) months after the Optionee's death, by the executors or
administrators of his or her estate or by any person or persons who acquire the
Option by will or the laws of descent and distribution, but not beyond the
otherwise applicable term of the Option.

          (j)  Disability of Optionee.
               ----------------------

               If an Optionee ceases to be an Employee due to becoming totally
and permanently disabled within the meaning of Section 22(e)(3) of the Code, any
Option granted to the Optionee may be exercised to the extent it had vested at
the time of cessation and, subject to the Plan, at any time within twelve (12)
months after the Optionee's termination of employment, but not beyond the
otherwise applicable term of the Option.

          (k)  Rights as a Shareholder.
               -----------------------

               An Optionee, or a transferee of an Optionee, shall have no rights
as a shareholder of the Corporation with respect to any Shares for which his or
her Option is exercisable until the date of the issuance of a stock certificate
for such Shares. No

                                       10
<PAGE>

adjustment shall be made for dividends, ordinary or extraordinary or whether in
currency, securities, or other property, distributions, or other rights for
which the record date is prior to the date such stock certificate is issued,
except as provided in Section 9 hereof.

          (l)  Modification, Extension, and Renewal of Options.
               -----------------------------------------------

               Within the limitations of the Plan, the Committee may modify,
extend or renew outstanding Options or accept the cancellation of outstanding
Options for the granting of new Options in substitution therefor.
Notwithstanding the preceding sentence, no modification of an Option shall,
without the consent of the Optionee, alter or impair any rights or obligations
under any Option previously granted.

          (m)  Return of Proceeds.
               ------------------

               (i)   The Committee, in its discretion, may include as a term of
any Optionee's stock option agreement a provision that, if within one year after
ceasing to be an Employee or Consultant (whether voluntarily or involuntarily),
an Optionee shall, directly or indirectly, engage in an activity that competes
with the business of the Corporation or a Subsidiary as conducted at the time
the Optionee ceased to be an Employee or Consultant (as determined by the Board
of Directors in its sole discretion and good faith) and such Optionee had
exercised Options within six months before or after the date the Optionee ceased
to be an Employee or Consultant, the Optionee shall be required to remit to the
Corporation in good funds within 5 business days of receipt of written demand
therefore an amount equal to the excess of (A) the Fair Market Value per share
of Common Stock on the date of exercise of such Option(s) multiplied by the
number of shares with respect to which the Options were exercised over (B) the
aggregate option exercise price for such number of shares of Common Stock (the
"Proceeds").

               (ii)  The Committee, in its discretion, may include as a term of
any Optionee's stock option agreement a provision requiring the remittance by an
Optionee to the Corporation in good funds within 5 business days of receipt of
written demand therefore of Proceeds by an Optionee that has exercised Options
within six months before or after the date the Optionee ceased to be an Employee
or Consultant (whether voluntarily or involuntarily). The Committee shall have
the authority in its discretion to include such other conditions and/or terms in
an Optionee's stock option agreement that it deems appropriate or desirable in
furtherance of the foregoing provisions.

          (n)  Other Provisions.
               ----------------

               The stock option agreements authorized under the Plan may contain
such other provisions which are not inconsistent with the terms of the Plan,
including, without limitation, restrictions upon the exercise of the Option, as
the Committee shall deem advisable.

                                       11
<PAGE>

     7.   $100,000 PER YEAR LIMITATION ON VESTING OF ISOs.
          -----------------------------------------------

          To the extent that the Fair Market Value of Shares (determined for
each Share as of the date of grant of the Option covering such Share) subject to
Options granted under this Plan (or any other plan of the Corporation or any
Affiliate) which are designated as Incentive Stock Options and which become
exercisable by an Optionee for the first time during a single calendar year
exceeds One Hundred Thousand United States Dollars (US$100,000), the Option(s)
(or portion thereof) covering such Shares shall be recharacterized (to the
extent of such excess over One Hundred Thousand United States Dollars
(US$100,000)) as a Nonstatutory Stock Option.  In determining which Option(s)
shall be treated as Nonstatutory Stock Options under the preceding sentence, the
Options shall be taken into account in the order granted, with the result that a
later granted Option shall be recharacterized as a Nonstatutory Stock Option
prior to such recharacterization of a previously granted Option.


     8.   TERM OF PLAN.
          ------------

          Awards may be granted pursuant to the Plan until ten (10) years
following the Effective Date or the date the Plan is approved by the
shareholders of the Corporation, whichever is earlier, and all Options which are
outstanding on such date shall remain in effect until they are exercised or
expire by their terms and shall continue to be subject to the provisions of the
Plan.


     9.   RECAPITALIZATION, TAKEOVERS, AND LIQUIDATIONS.
          ---------------------------------------------

          (a)  Reorganizations.
               ---------------

               The number of Shares covered by the Plan, as provided in Section
5 hereof, and the number of Shares for which each Option is exercisable shall be
proportionately adjusted for any increase or decrease in the number of issued
Shares resulting from the payment of a Common Stock dividend, a stock split, a
reverse stock split, recapitalization, combination, reclassification or any
other event which results in an increase or decrease in the number of issued
Shares effected without receipt of consideration by the Corporation, and the
Exercise Price shall be proportionately increased in the event the number of
Shares subject to such Option are decreased and shall be proportionately
decreased in the event the number of Shares subject to such Option are
increased. For the purposes of this paragraph, conversion of any convertible
securities of the Corporation shall not be deemed to have been "effected without
receipt of consideration." Adjustments shall be made by the Board, whose
determination in that respect shall be final, binding and conclusive. Except as
expressly provided herein, no issuance by the Corporation of shares of stock of
any class, or securities convertible into shares of stock of any class, shall
affect, and no adjustment by reason thereof shall be

                                       12
<PAGE>

made with respect to, the number or price of shares of Common Stock subject to
an Option.

          (b)  Liquidation.
               -----------

               In the event of the dissolution or liquidation of the
Corporation, each Option shall terminate immediately prior to the consummation
of such action. The Committee shall notify the Optionee not less than fifteen
(15) days prior to the proposed consummation of a pending dissolution or
liquidation, and the Option shall be exercisable as to all Shares which are
vested prior to expiration until immediately prior to the consummation of such
action.

          (c)  Merger.
               ------

               In the event of a consolidation or merger of the Corporation with
another corporation, or the sale of all or substantially all of its assets to
another corporation, or other similar event shall be effected, then, as a
condition of such consolidation, merger, or sale, lawful and fair provision
shall be made whereby the Option holders shall thereafter have the right to
purchase and receive, upon the basis and upon the terms and conditions specified
in the Plan and the stock option agreements and in lieu of the shares of Common
Stock of the Corporation immediately theretofore purchasable and receivable upon
the exercise of the rights represented thereby, such shares of stock,
securities, or assets as may be issued or payable with respect to or in exchange
for the number of outstanding shares of such Common Stock equal to the number of
shares of such stock immediately theretofore purchasable and receivable upon the
exercise of the rights represented by such Options, had such consolidation,
merger, or sale not taken place, and in such event appropriate provision shall
be made with respect to the rights and interests of the Option holders to the
end that the provisions hereof (including, without limitation, provisions for
adjustments of the exercise price and of the number of shares purchasable upon
the exercise of such Options) shall thereafter be applicable, as nearly as may
be in relation to any share of stock, securities, or assets thereafter
deliverable upon the exercise hereof; provided, however, that any and all
outstanding Options shall upon the occurrence of such event (if such event is
consummated on or after September 1, 2000) be automatically and immediately
fully vested.

          (d)  Determination by Committee.
               --------------------------

               All adjustments described in this Section 9 shall be made by the
Committee, whose determination shall be conclusive and binding on all persons.

          (e)  Limitation on Rights of Optionee.
               --------------------------------

               Except as expressly provided in this Section 9, no Optionee shall
have any rights by reason of any payment of any stock dividend, stock split or
reverse

                                       13
<PAGE>

stock split or any other increase or decrease in the number of shares of stock
of any class, or by reason of any reorganization, consolidation, dissolution,
liquidation, merger, exchange, split-up or reverse split-up, or spin-off of
assets or stock of another corporation. Any issuance by the Corporation of
Shares, Options or securities convertible into Shares or Options shall not
affect, and no adjustment by reason thereof shall be made with respect to, the
number or Exercise Price of the Shares for which an Option is exercisable.
Notwithstanding the foregoing, if the Corporation shall enter into a transaction
affecting the Corporation's capital stock or distributions to the holders of its
capital stock for which a revision in the terms of each Option is not required
pursuant to this Section 9, the Committee shall revise the terms of each Option
in a manner the Committee deems fair and reasonable in its sole discretion given
the transaction involved. If necessary or appropriate in connection with such
transaction, the Committee may declare that any Option shall terminate as of a
date fixed by the Committee and give each Optionee the right to exercise his or
her Option in whole or in part, including exercise as to Shares to which the
Option would not otherwise be exercisable.

          (f)  Stock Dividend; Distribution of Assets.
               --------------------------------------

               In the event of a stock dividend or other distribution of assets
by the Corporation to the holders of the Common Stock which is not covered by
any provision of this Section 9, the Option holders shall be entitled thereafter
to receive upon exercise of this Option the kind and amount of such
distribution, whether cash, shares of stock or other securities or assets, which
the Option holder would have been entitled to receive after the occurrence of
such event had this Option been exercised immediately prior to such event.

          (g)  No Restriction on Rights of Corporation.
               ---------------------------------------

               The grant of an Option shall not affect or restrict in any way
the right or power of the Corporation to make adjustments, reclassifications,
reorganizations, or changes of its capital or business structure, or to merge or
consolidate, or to dissolve, liquidate, sell, or transfer all or any part of its
business or assets.

     10.  SECURITIES LAW REQUIREMENTS.
          ---------------------------

          (a)  Legality of Issuance.
               --------------------

               No Share shall be issued upon the exercise of any Option unless
and until the Corporation has determined that:

               (i)   The Corporation and the Optionee have taken all actions
required to exempt the issuance of the Shares from the registration requirements
under the Securities Act of 1933, as amended (the "Act"), or the Corporation and
the Optionee shall determine that the registration requirements of the Act do
not apply to such exercise;

                                       14
<PAGE>

               (ii)  Any applicable listing requirement of any stock exchange on
which the Common Stock is listed has been satisfied; and

               (iii) Any other applicable provision of federal or state law has
been satisfied.

          (b)  Restrictions on Transfer; Representations of Optionee; Legends.
               --------------------------------------------------------------

               Regardless of whether the offering and sale of Shares has been
registered under the Act or has been registered or qualified under the
securities laws of any state, the Corporation may impose restrictions upon the
sale, pledge, or other transfer of such Shares, including the placement of
appropriate legends on stock certificates, if, in the judgment of the
Corporation and its counsel, such restrictions are necessary or desirable in
order to achieve compliance with the provisions of the Act, the securities laws
of any state, or any other law.  If the sale of Shares is not registered under
the Act and the Corporation shall determine that the registration requirements
of the Act apply to such sale, but an exemption is available which requires an
investment representation or other representation, the Optionee shall be
required, as a condition to purchasing Shares by exercise of his or her Option,
to represent that such Shares are being acquired for investment, and not with a
view to the sale or distribution thereof, except in compliance with the Act, and
to make such other representations as are deemed necessary or appropriate by the
Corporation and its counsel.  Stock certificates evidencing Shares acquired
pursuant to an unregistered transaction to which the Act applies shall bear a
restrictive legend substantially in the following form and such other
restrictive legends as are required or deemed advisable under the Plan or the
provisions of any applicable law:

          "THE SHARES REPRESENTED BY THIS CERTIFICATE HAVE NOT
          BEEN REGISTERED UNDER THE SECURITIES ACT OF 1933, AS
          AMENDED (THE "ACT"), OR QUALIFIED UNDER THE
          SECURITIES LAWS OF ANY STATE. THESE SHARES HAVE BEEN
          ACQUIRED FOR INVESTMENT AND NOT WITH A VIEW TO OR FOR
          SALE IN CONNECTION WITH ANY DISTRIBUTION THEREOF, AND
          MAY NOT BE SOLD, MORTGAGED, PLEDGED, HYPOTHECATED OR
          OTHERWISE TRANSFERRED WITHOUT AN EFFECTIVE
          REGISTRATION UNDER THE ACT AND/OR QUALIFICATION UNDER
          ANY APPLICABLE STATE SECURITIES LAWS, OR WITHOUT AN
          OPINION OF COUNSEL ACCEPTABLE TO THE CORPORATION AND
          ITS COUNSEL THAT SUCH REGISTRATION OR QUALIFICATION
          IS NOT REQUIRED."

                                       15
<PAGE>

The Corporation shall also place legends on stock certificates representing its
right of repurchase under Section 11 hereof and the right of first refusal under
Section 12 hereof.  Any determination by the Corporation and its counsel in
connection with any of the matters set forth in this Section 10 shall be
conclusive and binding on all persons.

          (c)  Registration or Qualification of Securities.
               -------------------------------------------

               The Corporation may, but shall not be obligated to, register or
qualify the sale of Shares under the Act or any other applicable law. In
connection with any such registration or qualification, the Corporation shall
provide each Optionee with such information required pursuant to all applicable
laws and regulations.

          (d)  Exchange of Certificates.
               ------------------------

               If, in the opinion of the Corporation and its counsel, any legend
placed on a stock certificate representing Shares sold hereunder is no longer
required, the Optionee or the holder of such certificate shall be entitled to
exchange such certificate for a certificate representing the same number of
Shares but lacking such legend.

          (e)  Market Standoff Agreement.
               -------------------------

               By acceptance of an Option, each Optionee agrees that if so
requested by the Corporation or any representative of the underwriters in
connection with any registration of any securities of the Corporation under the
Act, Optionee shall not sell or otherwise transfer any of the Shares or other
securities of the Corporation during the period requested by the Corporation or
the representative of the underwriters, as the case may be. Each Optionee agrees
that the Corporation may impose stop-transfer instructions with respect to the
securities subject to the foregoing restrictions.


     11.  RIGHT OF REPURCHASE.
          -------------------

          (a)  Repurchase Right.
               ----------------

               At the Committee's discretion, Shares issued pursuant to the
exercise of an Option may be subject to a right, but not an obligation, of
repurchase by the Corporation (the "Right of Repurchase"), at the price
specified in Section 11(b), if the Optionee ceases to be an Employee for any
reason ("Employment Termination") at any time after the grant of the Option
pursuant to which such Shares were issued. Shares issued by the Corporation
shall only be transferable by the Optionee subject to the Right of Repurchase,
and the Corporation shall legend the Right of Repurchase on the stock
certificates evidencing such Shares and shall take such other steps as it deems
necessary to ensure compliance with this restriction. The Corporation's rights
under this Section 11(a) shall be freely assignable, in whole or in part.

                                       16
<PAGE>

          (b)  Repurchase Price.
               ----------------

               The price per Share at which the Corporation may exercise the
Right of Repurchase under Section 11(a) (the "Repurchase Price") shall be the
Fair Market Value of the Shares on the date of the Employment Termination.

          (c)  Repurchase Procedure.
               --------------------

               The Corporation may exercise its Right of Repurchase by sending a
written notice to the Optionee and to the Escrow Agent, if any, of its taking
such action and specifying the number of Shares being repurchased. The Right of
Repurchase shall be exercised for cash or cancellation of purchase money
indebtedness for the Shares. The Corporation's Right of Repurchase shall
terminate (i) if not exercised by written notice from the Corporation to the
Optionee within ninety (90) days of the date of the Employment Termination, or
(ii) when the Corporation's securities become publicly traded. If the
Corporation exercises its Right of Repurchase, the Optionee, or if applicable,
the Escrow Agent, shall deliver to the Corporation every stock certificate
representing the Shares being repurchased, together with appropriate Assignments
separate from Certificates, and the Corporation shall then promptly pay the
total Repurchase Price, or if applicable, the difference between the total
Repurchase Price and any outstanding purchase money indebtedness of the Optionee
for the Shares, in cash to the Optionee, or if applicable, to the Escrow Agent,
for delivery to the Optionee.

          (d)  Election to Defer Purchase of Incentive Stock Option Shares.
               -----------------------------------------------------------

               (i)   Notwithstanding the preceding provisions of this Section
11, an Optionee whose Shares were issued pursuant to an Incentive Stock Option
may elect to defer the Corporation's repurchase of such Shares pursuant to this
Section 11 until the holding period requirements of Section 422(a) of the Code
are met. Such election shall be in writing in such form as the Committee may
require and shall be delivered to the Corporation and to the Escrow Agent by
certified mail no later than seven (7) days after the date on which the Optionee
receives notice that the Corporation elects to exercise its Right of Repurchase.
Such election shall pertain to all such Shares issued to the Optionee and shall
be irrevocable.

               (ii)  With respect to an Optionee who makes the election
described in subsection 11(d)(i), the Corporation shall repurchase such Shares
on or before the date which is ninety (90) days following the earlier of the
date on which the Optionee dies or the date on which the holding period
requirements of Section 422(a) of the Code are met. The Repurchase Price of each
such Share determined under Section 11(b) shall be calculated by substituting
for the Optionee's Employment Termination date the earlier of the date on which
the Optionee dies or the date on which such holding period requirements are met.

                                       17
<PAGE>

          (e)  Escrow.
               ------

               To facilitate the consummation of the Corporation's Right of
Repurchase under this Section 11, at the request of the Committee, the Optionee
and the Corporation shall execute Joint Escrow Instructions and the Optionee
shall deliver and deposit with the Escrow Agent named in the Joint Escrow
Instructions two "Assignments Separate from Certificate," together with all
certificates evidencing the Shares of Common Stock issued to the Optionee
pursuant to the Plan, duly endorsed in blank. The Escrow Agent shall hold such
documents and deliver the same to the Corporation pursuant to the Joint Escrow
Instructions and in accordance with the terms of this Section 11, as applicable.

          (f)  Binding Effect.
               --------------

               The Corporation's Right of Repurchase shall inure to the benefit
of its successors and assigns and shall be binding upon any representative,
executor, administrator, heir, or legatee of the Optionee.

          (g)  Payment of Net Amount Owing.
               ---------------------------

               Notwithstanding anything to the contrary contained herein, if the
Corporation determines to exercise its rights of repurchase pursuant to this
Section before any Shares have been issued as a result of an exercise of an
Option, in lieu of issuing any Shares, the Corporation shall have the right, but
not the obligation, to pay to the Optionee the net amount owing to the Optionee.

          (h)  Termination of Right of Repurchase.
               ----------------------------------

               Notwithstanding any other provision of this Section 11, in the
event that the Common Stock is listed on any United States securities exchange
or market or traded on any formal over-the-counter market in general use in the
United States at the time the Optionee would otherwise be required to transfer
his or her Shares, the Corporation shall no longer have the Right of Repurchase,
and the Optionee shall have no obligation to comply with this Section 11.


     12.  RIGHT OF FIRST REFUSAL.
          ----------------------

          (a)  Right of First Refusal.
               ----------------------

               At the Committee's discretion, Shares issued pursuant to the
exercise of an Option may be subject to a requirement that if an Optionee
proposes to sell, pledge, or otherwise transfer any Shares acquired pursuant to
exercise of an Option, or any interest in such Shares, to any person or entity,
the Corporation shall have a right of first refusal (the "Right of First
Refusal") with respect to such Shares. Any Optionee

                                       18
<PAGE>

desiring to transfer Shares subject to the Right of First Refusal shall give a
written notice (the "Transfer Notice") to the Corporation describing fully the
proposed transfer, including the number of Shares proposed to be transferred,
the proposed transfer price, and the name and address of the proposed
transferee. The Transfer Notice shall be signed both by the Optionee and by the
proposed transferee and must constitute a binding commitment of both parties to
the transfer of the Shares. The Corporation shall have the right to purchase the
Shares subject to the Transfer Notice on the terms of the proposal referred to
in the Transfer Notice, subject to any change in such terms permitted under
Section 12(b) hereof, by delivery of a notice of exercise of the Right of First
Refusal within thirty (30) days after the date the Transfer Notice is received
by the Corporation. The Corporation's rights under this Section 12(a) shall be
freely assignable, in whole or in part.

          (b)  Transfer of Shares.
               ------------------

               If the Corporation fails to exercise the Right of First Refusal
within thirty (30) days after the date on which it receives the Transfer Notice,
the Optionee may, not later than six (6) months following receipt of the
Transfer Notice by the Corporation, consummate a transfer of the Shares subject
to the Transfer Notice on the terms and conditions described in the Transfer
Notice. Any proposed transfer on terms and conditions different from those
described in the Transfer Notice, as well as any subsequent proposed transfer by
the Optionee, shall again be subject to the Right of First Refusal and shall
again require compliance with the procedure described in Section 12(a). If the
Corporation exercises its Right of First Refusal, the Optionee shall immediately
endorse and deliver to the Corporation every stock certificate representing the
Shares being purchased, and the Corporation shall then promptly pay the purchase
price in accordance with the terms set forth in the Transfer Notice.

          (c)  Repurchase Payment.
               ------------------

               The amount payable to an Optionee pursuant to the Corporation's
exercise of the Right of First Refusal shall be paid to the Optionee in
accordance with the terms and conditions of the Transfer Notice or may, at the
election of the Corporation, be paid in full in cash.

          (d)  Binding Effect.
               --------------

               The Corporation's Right of First Refusal shall inure to the
benefit of its successors and assigns and shall be binding upon any transferee
of the Shares.

          (e)  Termination of Right of First Refusal.
               -------------------------------------

               Notwithstanding any other provision of this Section 12, if the
Common Stock is listed on any United States securities exchange or market or
traded on any formal over-the-counter market in general use in the United States
at the time the

                                       19
<PAGE>

Optionee desires to transfer his or her Shares, the Corporation shall no longer
have the Right of First Refusal, and the Optionee shall have no obligation to
comply with this Section 12.


     13.  EXERCISE OF UNVESTED OPTIONS.
          ----------------------------

          The Committee may grant any Optionee the right to exercise any Option
prior to the complete vesting of such Option.  Without limiting the generality
of the foregoing, the Committee may provide that if an Option is exercised prior
to having completely vested, the Shares issued upon such exercise shall remain
subject to vesting at the same rate as under the Option so exercised and shall
be subject to a right, but not an obligation, of repurchase by the Corporation
with respect to all unvested Shares if the Optionee ceases to be an Employee for
any reason.  For the purposes of facilitating the enforcement of any such right
of repurchase, at the request of the Committee, the Optionee shall enter into
the Joint Escrow Instructions with the Corporation and deliver every certificate
for his or her unvested Shares with Assignments Separate from Certificate duly
executed in blank by the Optionee and by the Optionee's spouse, if required for
transfer.


     14.  AMENDMENT OF THE PLAN.
          ---------------------

          The Board or the Committee may, from time to time, terminate, suspend
or discontinue the Plan, in whole or in part, or revise or amend it in any
respect whatsoever including, but not limited to, the adoption of any
amendment(s) deemed necessary or advisable to qualify the Awards under rules and
regulations promulgated by the Securities and Exchange Commission with respect
to Employees who are subject to the provisions of Section 16 of the Securities
Exchange Act of 1934, as amended, or to correct any defect or supply any
omission or reconcile any inconsistency in the Plan or in any Award granted
thereunder, without approval of the shareholders of the Corporation, but without
the approval of the Corporation's shareholders, no such revision or amendment
shall:

               (i)   Increase the number of Shares subject to the Plan, other
than any increase pursuant to Section 9;

               (ii)  Materially modify the requirements as to eligibility for
participation in the Plan;

               (iii) Materially increase the benefits accruing to Optionees
under the Plan;

               (iv)  Extend the term of the Plan; or

                                       20
<PAGE>

               (v)   Amend this Section 14 to defeat its purpose.

No amendment, termination or modification of the Plan shall affect any Option
theretofore granted in any material adverse way without the consent of the
Optionee.


     15.  APPLICATION OF FUNDS.
          --------------------

          The proceeds received by the Corporation from the sale of Common Stock
pursuant to the exercise of an Option shall be used for general corporate
purposes.


     16.  APPROVAL OF SHAREHOLDERS.
          ------------------------

          The Plan shall be subject to approval by the affirmative vote of the
holders of a majority of all classes of the outstanding stock present and
entitled to vote at the first meeting of shareholders of the Corporation
following the adoption of the Plan or by written consent, and in no event later
than one (1) year following the Effective Date.  Prior to such approval, Options
may be granted but shall not be exercisable.  Any amendment described in Section
14 (i) to (v) shall also be subject to approval by the Corporation's
shareholders.


     17.  WITHHOLDING OF TAXES.
          --------------------

          In the event the Corporation or a Affiliate determines that it is
required to withhold federal, state, or local taxes in connection with the
exercise of an Option or the disposition of Shares issued pursuant to the
exercise of an Option, the Optionee or any person succeeding to the rights of
the Optionee, as a condition to such exercise or disposition, may be required to
make arrangements satisfactory to the Corporation or the Affiliate to enable it
to satisfy such withholding requirements.


     18.  RIGHTS AS AN EMPLOYEE.
          ---------------------

          Neither the Plan nor any Option granted pursuant thereto shall be
construed to give any person the right to remain in the employ of the
Corporation or any Affiliate, or to affect the right of the Corporation or any
Affiliate to terminate such individual's employment at any time with or without
cause.  The grant of an Option shall not entitle the Optionee to, or disqualify
the Optionee from, participation in the grant of any other Option under the Plan
or participation in any other benefit plan maintained by the Corporation or any
Affiliate.

                                       21
<PAGE>

     19.  DISAVOWAL OF REPRESENTATIONS, UNDERTAKINGS OR CREATION OF IMPLIED
          -----------------------------------------------------------------
RIGHTS.
-------

          In adopting and maintaining this Plan and granting Awards hereunder,
neither the Corporation nor any Affiliate makes any representations or
undertakings with respect to the initial qualification or treatment of the
Awards under federal or state tax or securities laws.  The Corporation and each
Affiliate expressly disavows the creation of any rights in Employees, Optionees,
or beneficiaries of any obligations on the part of the Corporation, any
Affiliate or the Committee, except as expressly provided herein.


     20.  INSPECTION OF RECORDS.
          ----------------------

          Copies of the Plan, records reflecting each Optionee's Option, and any
other documents and records which an Optionee is entitled by law to inspect
shall be open to inspection by the Optionee and his or her duly authorized
representative at the office of the Committee at any reasonable business hour.


     21.  INFORMATION TO OPTIONEES.
          ------------------------

          Each Optionee shall be provided with such information regarding the
Corporation as the Committee from time to time deems necessary or appropriate;
provided however, that each Optionee shall at all times be provided with such
information as is required to be provided from time to time pursuant to
applicable regulatory requirements, including, but not limited to, any
applicable requirements of the Securities and Exchange Commission and other
state securities agencies.


     22.  NON-U.S. ELIGIBLE INDIVIDUALS AND AFFILIATES.  Notwithstanding any
          --------------------------------------------
provision of the Plan to the contrary, in order to foster and promote
achievement of the purposes of the Plan or to comply with provisions of laws in
other countries in which the Corporation or its Affiliates operate or have
employees, the Committee, in its discretion, shall have the power and authority
to (i) determine which (if any) Employees rendering services or employed outside
the United States are eligible to participate in the Plan or any type of Award
granted hereunder; (ii) determine which non-United States-based Affiliates or
operations (e.g., branches, representative offices) participate in the Plan or
any type of Award hereunder; (iii) modify the terms and conditions of any Awards
made to such eligible Employees, or with respect to such non-United States-based
Affiliates or operations; and (iv) establish subplans, modified exercise,
vesting, payment and other terms and procedures to the extent deemed necessary
or desirable by the Committee.

                                       22
<PAGE>

                                   EXHIBIT A


     THE SECURITIES REPRESENTED HEREBY HAVE NOT BEEN REGISTERED UNDER THE
     SECURITIES ACT OF 1933, AS AMENDED, AND MAY NOT BE SOLD, PLEDGED, OR
     OTHERWISE TRANSFERRED WITHOUT AN EFFECTIVE REGISTRATION THEREOF
     UNDER SUCH ACT OR AN OPINION OF COUNSEL, SATISFACTORY TO THE
     CORPORATION AND ITS COUNSEL, THAT SUCH REGISTRATION IS NOT REQUIRED.


                      NONSTATUTORY STOCK OPTION AGREEMENT

     This Stock Option Agreement is made and entered into this ___ day of March,
2000, pursuant to the DataVoN Inc. 2000 Stock Option Plan (the "Plan"). The
Board administering the Plan has selected _________________________________("the
Optionee") to receive the following grant of a nonstatutory stock option (the
"Stock Option") to purchase shares of the common stock of DataVoN Inc, a Texas
corporation (the "Corporation"), on the terms and conditions set forth below to
which Optionee accepts and agrees:

     1.   Stock Options Granted:

          No. of Shares Subject to Option.......____________________
          Date of Grant.........................March ___, 2000
          Vesting Commencement Date.............____________________
          Exercise Price Per Share..............____________________
               Expiration Date..................March ___, 2010

     2.   The Stock Option is granted pursuant to the Plan to purchase the
number of shares of authorized but unissued common stock of the Corporation
specified in Section 1 hereof (the "Shares").  The Stock Option shall expire,
and all rights to exercise it shall terminate on the Expiration Date, except
that the Stock Option may expire earlier as provided in the Plan or this
Agreement.  The number of shares subject to the Stock Option granted hereunder
shall be adjusted as provided in the Plan.  The Stock Option is intended by the
Corporation and the Optionee to be a Nonstatutory Stock Option and does not
qualify for any special tax benefits to the Optionee and is not subject to
Section 7 of the Plan.

     3.   The Stock Option shall be exercisable in all respects in accordance
with the terms of the Plan which are incorporated herein by this reference.
Optionee acknowledges having received and read a copy of the Plan.  All shares
of the Corporation's common stock issued pursuant to the exercise of the Stock
Option shall be

                                       23
<PAGE>

subject to the Corporation's Right of Repurchase and Right of First Refusal as
set forth in Sections 11 and 12 of the Plan.

     4.   Optionee shall have the right to exercise the Stock Option in
accordance with the following schedule:

          (a) The Stock Option may not be exercised in whole or in part at any
time prior to the end of the first four (4) full calendar quarters following the
Vesting Commencement Date.

          (b) Optionee may exercise the Stock Option as to one third (1/3rd) of
the Shares at the end of the fourth (4/th/) full calendar quarter following the
Vesting Commencement Date.

          (c) Optionee may exercise the Stock Option as to an additional one
twelfth (1/12/th/) of the Shares at the end of each of the full calendar quarter
commencing with the fifth (5/th/) full calendar quarter following the Vesting
Commencement Date.

          (d) The right to exercise the Stock Option shall be cumulative.
Optionee may buy all, or from time to time any part, of the maximum number of
Shares which are exercisable under the Stock Option, but in no case may Optionee
exercise the Stock Option with regard to a fraction of a Share, or for any Share
for which the Stock Option is not exercisable.

     5.   Employee agrees to return to the Corporation in good funds within five
business days of receipt of written demand therefor, an amount equal to the
excess of (A) the Fair Market Value per Share of Common Stock on the date of
exercise of any Stock Options under this Agreement multiplied by the number of
Shares so purchased upon such exercise over (B) the aggregate price paid for the
Shares of Common Stock as to which such Stock Option was exercised if (a)
Optionee ceases to be an employee of the Corporation or a Subsidiary for any
reason (whether voluntary or involuntary), exercises Stock Options hereunder
within six months before or after the date employment ceases, and, within one
year after such employment ceases, directly or indirectly engages in an activity
that competes with the business of the Corporation or a Subsidiary as conducted
at the time of such termination of employment (as determined by the Board in its
sole discretion and good faith) or (b) Optionee ceases to be an employee
voluntarily or by reason of discharge "for Cause" (as defined below) and if
Optionee exercises Stock Options hereunder within six months before or after the
date of termination of employment.  Amounts due the Corporation pursuant to this
paragraph are payable by Optionee in Dallas County, Texas.  If Optionee fails to
return the proceeds as required by this paragraph and the Corporation shall
institute litigation to enforce or interpret its rights, Optionee shall pay (i)
the Corporation for its reasonable attorney's fees, disbursements and other
costs incurred in enforcing or interpreting Optionee's obligation and (ii)
interest on the amount due the Corporation at a rate of eighteen percent (18%)
per

                                       24
<PAGE>

annum (or at the then highest legal rate in Texas) from the date such amount
became due until paid.

     For purposes of this Agreement, termination "for Cause" shall mean the
Corporation's termination of Optionee's employment with the Corporation due to:
(a) consistent and material violation of the Corporation's policies and
procedures; (b) material violation of any material law, rule, or regulation; (c)
conduct involving moral turpitude or adverse to the public image of the
Corporation; (d) action in the aid of a competitor, vendor, or supplier of the
Corporation to the disadvantage of the Corporation; (e) material
misrepresentation or false statements on any document to the Corporation in
connection with Optionee's hiring or commencement of Optionee's employment with
the Corporation; (f) misappropriation of funds or assets of the Corporation; or
(g) Optionee's willful refusal to perform Optionee's duties or to comply with
the Corporation's (or the Board's) directions or instructions.

     6.   The Optionee agrees to comply with all laws, rules, and regulations
applicable to the grant and exercise of the Stock Option and the sale or other
disposition of the common stock of the Corporation received pursuant to the
exercise of such Stock Option.

     7.   The Stock Option shall not become exercisable unless and until the
Shares exercisable under the Stock Option have been qualified under any
applicable securities laws or unless the exercise is otherwise exempt from the
qualification requirements of such law.  The Stock Option is conditioned upon
the Optionee's representation, which Optionee hereby confirms as of the date
hereof and which Optionee must confirm as of the date of any exercise of all or
any part of the Stock Option, that:

          (a)  Optionee understands that both the Stock Option and any Shares
purchased upon its exercise are securities, the issuance of which require
compliance with federal and state securities laws;

          (b)  Optionee understands that the securities have not been registered
under the Securities Act of 1933 (the "Act") in reliance upon a specific
exemption contained in the Act which depends upon Optionee's bona fide
investment intention in acquiring these securities; that Optionee's intention is
to hold these securities for Optionee's own benefit for an indefinite period;
that Optionee has no present intention of selling or transferring any part
thereof (recognizing that the Stock Option is not transferable) and that certain
restrictions may exist on transfer of the Shares issued upon exercise of the
Stock Option;

          (c)  Optionee understands that the Shares issued upon exercise of the
Stock Option, in addition to other restrictions on transfer, must be held
indefinitely unless subsequently registered under the Act, or unless an
exemption from registration is available; that Rule 701 and Rule 144, two
exemptions from registration which may be available, are only available after
the satisfaction of certain conditions and require the

                                       25
<PAGE>

presence of a U.S. public market for such shares; that no certainty exists that
a U.S. public market for the shares will exist, and that otherwise Optionee may
have to sell the shares pursuant to another exemption from registration which
exemption may be difficult to satisfy; and

          (d)  The Corporation shall not be under any obligation to issue any
Shares upon the exercise of the Stock Option unless and until the Corporation
has determined that:

               (i)   it and Optionee have taken all actions required to register
such shares under the Securities Act, or to perfect an exemption from the
registration requirements thereof;

               (ii)  any applicable listing requirement of any stock exchange on
which such shares are listed has been satisfied; and

               (iii) all other applicable provisions of federal and state law
have been satisfied.

     8.   By entering into this Agreement and accepting the grant of the Stock
Option, the Optionee acknowledges that:

          (i)   the Plan is discretionary in nature and may be suspended or
terminated by the Corporation at any time;

          (ii)  the grant of the Stock Option is a one-time benefit which does
not create any contractual or other right to receive future grants of options,
or benefits in lieu of options; all determinations with respect to any such
future grants, including, but not limited to, the times when options shall be
granted, the number of shares subject to each option, the option price, and the
time or times when each option shall be exercisable, will be at the sole
discretion of the Corporation;

          (iii) the Optionee's participation in the Plan is voluntary;

          (iv)  the value of the Stock Option is an extraordinary item of
compensation which is outside the scope of the Optionee's employment contract,
if any;

          (v)   the Stock Option is not part of normal or expected compensation
for purposes of calculating any severance, resignation, redundancy, end of
service payments, bonuses, long-service awards, pension or retirement benefits
or similar payments;

          (vi)  the vesting of any of the Shares ceases upon termination of
employment for any reason except as may otherwise be explicitly provided in the
Plan document; and

                                       26
<PAGE>

          (vii)  the future value of the Stock Option's underlying Shares is
unknown and cannot be predicted with certainty, and if the underlying Shares do
not increase in value, the Stock Option will have no value.

     9.   By entering into this Agreement, the Optionee: (i) authorizes and
instructs the Corporation and, if applicable, the employer entity, and any agent
of the Corporation administering the Plan or providing Plan recordkeeping
services, to collect, process and transfer to the Corporation or any of its
affiliates such information and data as the Corporation shall request in order
to facilitate the grant of the Stock Option and the administration of the Plan;
(ii) waives any data privacy rights he or she may have with respect to such
information; and (iii) authorizes the Corporation and any such agent to store
and transmit such information in electronic form.


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<PAGE>

     IN WITNESS WHEREOF, each of the parties hereto has executed this Stock
Option Agreement, in the case of the Corporation by its duly authorized officer,
as of the date and year written above.


OPTIONEE                             DATAVON INC.



_____________________________        By:_____________________________
        (signature)                             (signature)


_____________________________        Its:____________________________
       (Type or Print Name)



Address: ____________________

_____________________________

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<PAGE>

                                   EXHIBIT B


     THE SECURITIES REPRESENTED HEREBY HAVE NOT BEEN REGISTERED UNDER THE
     SECURITIES ACT OF 1933, AS AMENDED, AND MAY NOT BE SOLD, PLEDGED, OR
     OTHERWISE TRANSFERRED WITHOUT AN EFFECTIVE REGISTRATION THEREOF UNDER SUCH
     ACT OR AN OPINION OF COUNSEL, SATISFACTORY TO THE CORPORATION AND ITS
     COUNSEL, THAT SUCH REGISTRATION IS NOT REQUIRED.


                       INCENTIVE STOCK OPTION AGREEMENT

     This Stock Option Agreement is made and entered into this ____ day of
March, 2000, pursuant to the DataVoN Inc. 2000 Stock Option Plan (the "Plan").
The Board administering the Plan has selected ______________("the Optionee") to
receive the following grant of an incentive stock option (the "Stock Option") to
purchase shares of the common stock of DataVoN Inc., a Texas corporation (the
"Corporation"), on the terms and conditions set forth below to which Optionee
accepts and agrees:

     1.   Stock Options Granted:

          No. of Shares Subject to Option.........._______________
          Date of Grant............................March ___, 2000
          Vesting Commencement Date................_______________
          Exercise Price Per Share................._______________
          Expiration Date..........................March ___, 2010

     2.   The Stock Option is granted pursuant to the Plan to purchase the
number of shares of authorized but unissued common stock of the Corporation
specified in Section 1 hereof (the "Shares").  The Stock Option shall expire,
and all rights to exercise it shall terminate on the Expiration Date, except
that the Stock Option may expire earlier as provided in the Plan or this
Agreement.  The number of Shares subject to the Stock Option granted hereunder
shall be adjusted as provided in the Plan.

     3.   The Stock Option shall be exercisable in all respects in accordance
with the terms of the Plan which are incorporated herein by this reference.
Optionee acknowledges having received and read a copy of the Plan.  All shares
of the Corporation's common stock issued pursuant to the exercise of this Stock
Option shall be subject to the Corporation's Right of Repurchase and Right of
First Refusal as set forth in Sections 11 and 12 of the Plan.

     4.   Optionee shall have the right to exercise the Stock Option in
accordance with the following schedule:

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<PAGE>

          (a)  The Stock Option may not be exercised in whole or in part at any
time prior to the end of the first four (4) full calendar quarters following the
Vesting Commencement Date.

          (b)  Optionee may exercise the Stock Option as to one third (1/3rd) of
the Shares at the end of the fourth (4/th/) full calendar quarter following the
Vesting Commencement Date.

          (c)  Optionee may exercise the Stock Option as to an additional one
twelfth (1/12/th/) of the Shares at the end of each of the full calendar quarter
commencing with the fifth (5/th/) full calendar quarter following the Vesting
Commencement Date.

          (d)  The right to exercise the Stock Option shall be cumulative.
Optionee may buy all, or from time to time any part, of the maximum number of
Shares which are exercisable under the Stock Option, but in no case may Optionee
exercise the Stock Option with regard to a fraction of a Share, or for any Share
for which the Stock Option is not exercisable.

     5.   Employee agrees to return to the Corporation in good funds within five
business days of receipt of written demand therefor, an amount equal to the
excess of (A) the Fair Market Value per Share of Common Stock on the date of
exercise of any Stock Options under this Agreement multiplied by the number of
Shares so purchased upon such exercise over (B) the aggregate price paid for the
Shares of Common Stock as to which such Stock Option was exercised if (a)
Optionee ceases to be an employee of the Corporation or a Subsidiary for any
reason (whether voluntary or involuntary), exercises Stock Options hereunder
within six months before or after the date employment ceases, and, within one
year after such employment ceases, directly or indirectly engages in an activity
that competes with the business of the Corporation or a Subsidiary as conducted
at the time of such termination of employment (as determined by the Board in its
sole discretion and good faith) or (b) Optionee ceases to be an employee
voluntarily or by reason of discharge "for Cause" (as defined below) and if
Optionee exercises Stock Options hereunder within six months before or after the
date of termination of employment.  Amounts due the Corporation pursuant to this
paragraph are payable by Optionee in Dallas County, Texas.  If Optionee fails to
return the proceeds as required by this paragraph and the Corporation shall
institute litigation to enforce or interpret its rights, Optionee shall pay (i)
the Corporation for its reasonable attorney's fees, disbursements and other
costs incurred in enforcing or interpreting Optionee's obligation and (ii)
interest on the amount due the Corporation at a rate of eighteen percent (18%)
per annum (or at the then highest legal rate in Texas) from the date such amount
became due until paid.

     For purposes of this Agreement, termination "for Cause" shall mean the
Corporation's termination of Optionee's employment with the Corporation due to:
(a)

                                       30
<PAGE>

consistent and material violation of the Corporation's policies and procedures;
(b) material violation of any material law, rule, or regulation; (c) conduct
involving moral turpitude or adverse to the public image of the Corporation; (d)
action in the aid of a competitor, vendor, or supplier of the Corporation to the
disadvantage of the Corporation; (e) material misrepresentation or false
statements on any document to the Corporation in connection with Optionee's
hiring or commencement of Optionee's employment with the Corporation; (f)
misappropriation of funds or assets of the Corporation; or (g) Optionee's
willful refusal to perform Optionee's duties or to comply with the Corporation's
(or the Board's) directions or instructions.

     6.   The Optionee agrees to comply with all laws, rules, and regulations
applicable to the grant and exercise of the Stock Option and the sale or other
disposition of the common stock of the Corporation received pursuant to the
exercise of such Stock Option.

     7.   The Stock Option shall not become exercisable unless and until the
Shares exercisable under the Stock Option have been qualified under any
applicable securities laws or unless the exercise is otherwise exempt from the
qualification requirements of such law.  The Stock Option is conditioned upon
the Optionee's representation, which Optionee hereby confirms as of the date
hereof and which Optionee must confirm as of the date of any exercise of all or
any part of the Stock Option, that:

          (a)  Optionee understands that both the Stock Option and any Shares
purchased upon its exercise are securities, the issuance of which require
compliance with federal and state securities laws;

          (b)  Optionee understands that the securities have not been registered
under the Securities Act of 1933 (the "Act") in reliance upon a specific
exemption contained in the Act which depends upon Optionee's bona fide
investment intention in acquiring these securities; that Optionee's intention is
to hold these securities for Optionee's own benefit for an indefinite period;
that Optionee has no present intention of selling or transferring any part
thereof (recognizing that the Stock Option is not transferable) and that certain
restrictions may exist on transfer of the Shares issued upon exercise of the
Stock Option;

          (c)  Optionee understands that the Shares issued upon exercise of the
Stock Option, in addition to other restrictions on transfer, must be held
indefinitely unless subsequently registered under the Act, or unless an
exemption from registration is available; that Rule 701 and Rule 144, two
exemptions from registration which may be available, are only available after
the satisfaction of certain conditions and require the presence of a U.S. public
market for such shares; that no certainty exists that a U.S. public market for
the shares will exist, and that otherwise Optionee may have to sell the shares
pursuant to another exemption from registration which exemption may be difficult
to satisfy; and

                                       31
<PAGE>

          (d)  The Corporation shall not be under any obligation to issue any
shares upon the exercise of the Stock Option unless and until the Corporation
has determined that:

               (i)   it and Optionee have taken all actions required to register
such shares under the Securities Act, or to perfect an exemption from the
registration requirements thereof;

               (ii)  any applicable listing requirement of any stock exchange on
which such shares are listed has been satisfied; and

               (iii) all other applicable provisions of federal and state law
have been satisfied.

                                       32
<PAGE>

     IN WITNESS WHEREOF, each of the parties hereto has executed this Stock
Option Agreement, in the case of the Corporation by its duly authorized officer,
as of the date and year written above.

OPTIONEE                                  DATAVON INC.


_____________________________             By:______________________________
        (signature)                                   (signature)

_____________________________             Its:_____________________________
        (Type or Print Name)

Address:_____________________

_____________________________

                                       33