Document:

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                                                                   EXHIBIT 10.39

                          REGISTRATION RIGHTS AGREEMENT

      REGISTRATION RIGHTS AGREEMENT (this "AGREEMENT"), dated as of _____ __,
2002, by and between PROBEX CORP., a Delaware corporation, (the "COMPANY"), and
FUSION CAPITAL FUND II, LLC (together with it permitted assigns, the "BUYER").
Capitalized terms used herein and not otherwise defined herein shall have the
respective meanings set forth in the Common Stock Purchase Agreement by and
between the parties hereto dated as of _______, 2002 (as amended, restated,
supplemented or otherwise modified from time to time, the "PURCHASE AGREEMENT").

                                    WHEREAS:

      A.    The Company has agreed, upon the terms and subject to the conditions
of the Purchase Agreement, to issue to the Buyer (i) up to Twenty Million
Dollars ($20,000,000) of the Company's common stock, par value $0.001 per share
(the "COMMON STOCK") (the "PURCHASE SHARES"), and (ii) such number of shares of
Common Stock as is required pursuant to Section 4(f) of the Purchase Agreement
(the "COMMITMENT SHARES"); and

      B.    To induce the Buyer to enter into the Purchase Agreement, the
Company has agreed to provide certain registration rights under the Securities
Act of 1933, as amended, and the rules and regulations thereunder, or any
similar successor statute (collectively, the "1933 ACT"), and applicable state
securities laws.

      NOW, THEREFORE, in consideration of the premises and the mutual covenants
contained herein and other good and valuable consideration, the receipt and
sufficiency of which are hereby acknowledged, the Company and the Buyer hereby
agree as follows:

      1.    DEFINITIONS.

            As used in this Agreement, the following terms shall have the
following meanings:

            a.    "INVESTOR" means the Buyer, any transferee or assignee thereof
to whom a Buyer assigns its rights under this Agreement and who agrees to become
bound by the provisions of this Agreement in accordance with Section 9 and any
transferee or assignee thereof to whom a transferee or assignee assigns its
rights under this Agreement and who agrees to become bound by the provisions of
this Agreement in accordance with Section 9.

            b.    "PERSON" means any person or entity including any corporation,
a limited liability company, an association, a partnership, an organization, a
business, an individual, a governmental or political subdivision thereof or a
governmental agency.

            c.    "REGISTER," "REGISTERED," and "REGISTRATION" refer to a
registration effected by preparing and filing one or more registration
statements of the Company in compliance with the 1933 Act and pursuant to Rule
415 under the 1933 Act or any successor rule providing for offering securities
on a continuous basis ("RULE 415"), and the declaration or ordering of
effectiveness of such registration statement(s) by the United States Securities
and Exchange Commission (the "SEC").
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            d.    "REGISTRABLE SECURITIES" means the Purchase Shares which have
been, or which may from time to time be, issued or issuable upon purchases of
the Available Amount under the Purchase Agreement (without regard to any
limitation or restriction on purchases) and the Commitment Shares issued or
issuable to the Investor and any shares of capital stock issued or issuable with
respect to the Purchase Shares, the Commitment Shares or the Purchase Agreement
as a result of any stock split, stock dividend, recapitalization, exchange or
similar event or otherwise, without regard to any limitation on purchases under
the Purchase Agreement.

            e.    "REGISTRATION STATEMENT" means the registration statement of
the Company which the Company has agreed to file pursuant to Section 4(a) of the
Purchase Agreement with respect to the sale of the Registrable Securities.

      2.    REGISTRATION.

            a.    Mandatory Registration. The Company shall use reasonable best
efforts to keep the Registration Statement effective pursuant to Rule 415
promulgated under the 1933 Act and available for sales of all of the Registrable
Securities at all times until the earlier of (i) the date as of which the
Investor may sell all of the Registrable Securities without restriction pursuant
to Rule 144(k) promulgated under the 1933 Act (or successor thereto) or (ii) the
date on which (A) the Investor shall have sold all the Registrable Securities
and no available amount remains under the Purchase Agreement (the "REGISTRATION
PERIOD"). The Registration Statement (including any amendments or supplements
thereto and prospectuses contained therein) shall not contain any untrue
statement of a material fact or omit to state a material fact required to be
stated therein, or necessary to make the statements therein, in light of the
circumstances in which they were made, not misleading.

            b.    Rule 424 Prospectus. The Company shall, as required by
applicable securities regulations, from time to time file with the SEC, pursuant
to Rule 424 promulgated under the 1933 Act, the prospectus and prospectus
supplements, if any, to be used in connection with sales of the Registrable
Securities under the Registration Statement. The Investor and its counsel shall
have a reasonable opportunity to review and comment upon such prospectus prior
to its filing with the SEC. The Investor shall use its reasonable best efforts
to comment upon such prospectus within one (1) Trading Day from the date the
Investor receives the final version of such prospectus.

            c.    Sufficient Number of Shares Registered. In the event the
number of shares available under the Registration Statement is insufficient to
cover all of the Registrable Securities, the Company shall amend the
Registration Statement or file a new registration statement (a "NEW REGISTRATION
STATEMENT"), so as to cover all of such Registrable Securities as soon as
practicable, but in any event not later than ten (10) Trading Days after the
necessity therefore arises. The Company shall use it reasonable best efforts to
cause such amendment and/or New Registration Statement to become effective as
soon as practicable following the filing thereof.

3.    RELATED OBLIGATIONS.

      With respect to the Registration Statement and whenever any Registrable
Securities are to be registered pursuant to Section 2(b) including on any New
Registration Statement, the Company shall use its reasonable best efforts to
effect the registration of the Registrable Securities in accordance with the
intended method of disposition thereof and, pursuant thereto, the Company shall
have the following obligations:

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            a.    The Company shall prepare and file with the SEC such
amendments (including post-effective amendments) and supplements to any
registration statement and the prospectus used in connection with such
registration statement, which prospectus is to be filed pursuant to Rule 424
promulgated under the 1933 Act, as may be necessary to keep the Registration
Statement or any New Registration Statement effective at all times during the
Registration Period, and, during such period, comply with the provisions of the
1933 Act with respect to the disposition of all Registrable Securities of the
Company covered by the Registration Statement or any New Registration Statement
until such time as all of such Registrable Securities shall have been disposed
of in accordance with the intended methods of disposition by the seller or
sellers thereof as set forth in such registration statement.

            b.    The Company shall permit the Investor to review and comment
upon the Registration Statement or any New Registration Statement and all
amendments and supplements thereto at least two (2) Trading Days prior to their
filing with the SEC, and not file any document in a form to which Investor
reasonably objects. The Investor shall use its reasonable best efforts to
comment upon the Registration Statement or any New Registration Statement and
any amendments or supplements thereto within two (2) Trading Days from the date
the Investor receives the final version thereof. The Company shall furnish to
the Investor, without charge any correspondence from the SEC or the staff of the
SEC to the Company or its representatives relating to the Registration Statement
or any New Registration Statement.

            c.    Upon request of the Investor, the Company shall furnish to the
Investor, (i) promptly after the same is prepared and filed with the SEC, at
least one copy of such registration statement and any amendment(s) thereto,
including financial statements and schedules, all documents incorporated therein
by reference and all exhibits, (ii) upon the effectiveness of any registration
statement, ten (10) copies of the prospectus included in such registration
statement and all amendments and supplements thereto (or such other number of
copies as the Investor may reasonably request) and (iii) such other documents,
including copies of any preliminary or final prospectus, as the Investor may
reasonably request from time to time in order to facilitate the disposition of
the Registrable Securities owned by the Investor.

            d.    The Company shall use reasonable best efforts to (i) register
and qualify the Registrable Securities covered by a registration statement under
such other securities or "blue sky" laws of such jurisdictions in the United
States as the Investor reasonably requests, (ii) prepare and file in those
jurisdictions, such amendments (including post-effective amendments) and
supplements to such registrations and qualifications as may be necessary to
maintain the effectiveness thereof during the Registration Period, (iii) take
such other actions as may be necessary to maintain such registrations and
qualifications in effect at all times during the Registration Period, and (iv)
take all other actions reasonably necessary or advisable to qualify the
Registrable Securities for sale in such jurisdictions; provided, however, that
the Company shall not be required in connection therewith or as a condition
thereto to (x) qualify to do business in any jurisdiction where it would not
otherwise be required to qualify but for this Section 3(d), (y) subject itself
to general taxation in any such jurisdiction, or (z) file a general consent to
service of process in any such jurisdiction. The Company shall promptly notify
the Investor who holds Registrable Securities of the receipt by the Company of
any notification with respect to the suspension of the registration or
qualification of any of the Registrable Securities for sale under the securities
or "blue sky" laws of any jurisdiction in the United States or its receipt of
actual notice of the initiation or threatening of any proceeding for such
purpose.

            e.    As promptly as practicable after becoming aware of such event
or facts, the Company shall notify the Investor in writing of the happening of
any event or existence of such facts as a

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result of which the prospectus included in any registration statement, as then
in effect, includes an untrue statement of a material fact or omits to state a
material fact required to be stated therein or necessary to make the statements
therein, in light of the circumstances under which they were made, not
misleading, and promptly prepare a supplement or amendment to such registration
statement to correct such untrue statement or omission, and deliver ten (10)
copies of such supplement or amendment to the Investor (or such other number of
copies as the Investor may reasonably request). The Company shall also promptly
notify the Investor in writing (i) when a prospectus or any prospectus
supplement or post-effective amendment has been filed, and when a registration
statement or any post-effective amendment has become effective (notification of
such effectiveness shall be delivered to the Investor by facsimile on the same
day of such effectiveness and by overnight mail), (ii) of any request by the SEC
for amendments or supplements to any registration statement or related
prospectus or related information, and (iii) of the Company's reasonable
determination that a post-effective amendment to a registration statement would
be appropriate.

            f.    The Company shall use its reasonable best efforts to prevent
the issuance of any stop order or other suspension of effectiveness of any
registration statement, or the suspension of the qualification of any
Registrable Securities for sale in any jurisdiction and, if such an order or
suspension is issued, to obtain the withdrawal of such order or suspension at
the earliest possible moment and to notify the Investor of the issuance of such
order and the resolution thereof or its receipt of actual notice of the
initiation or threat of any proceeding for such purpose.

            g.    The Company shall (i) cause all the Registrable Securities to
be listed on each securities exchange on which securities of the same class or
series issued by the Company are then listed, if any, if the listing of such
Registrable Securities is then permitted under the rules of such exchange, or
(ii) secure designation and quotation of all the Registrable Securities on the
[_____________]. The Company shall pay all fees and expenses in connection with
satisfying its obligation under this Section.

            h.    The Company shall cooperate with the Investor to facilitate
the timely preparation and delivery of certificates (not bearing any restrictive
legend) representing the Registrable Securities to be offered pursuant to any
registration statement and enable such certificates to be in such denominations
or amounts as the Investor may reasonably request and registered in such names
as the Investor may request.

            i.    The Company shall at all times provide a transfer agent and
registrar with respect to its Common Stock.

            j.    If reasonably requested by the Investor, the Company shall (i)
immediately incorporate in a prospectus supplement or post-effective amendment
such information as the Investor believes should be included therein relating to
the sale and distribution of Registrable Securities, including, without
limitation, information with respect to the number of Registrable Securities
being sold, the purchase price being paid therefore and any other terms of the
offering of the Registrable Securities; (ii) make all required filings of such
prospectus supplement or post-effective amendment as soon as notified of the
matters to be incorporated in such prospectus supplement or post-effective
amendment; and (iii) supplement or make amendments to any registration
statement.

            k.    The Company shall use its reasonable best efforts to cause the
Registrable Securities covered by the any registration statement to be
registered with or approved by such other governmental agencies or authorities
as may be necessary to consummate the disposition of such Registrable
Securities.

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            l.    Within one (1) Trading Day after any registration statement
which includes the Registrable Securities is ordered effective by the SEC, the
Company shall deliver, and shall cause legal counsel for the Company to deliver,
to the transfer agent for such Registrable Securities (with copies to the
Investor) confirmation that such registration statement has been declared
effective by the SEC in the form attached hereto as Exhibit A.

            m.    The Company shall take all other reasonable actions necessary
to expedite and facilitate disposition by the Investor of Registrable Securities
pursuant to any registration statement.

      4.    OBLIGATIONS OF THE INVESTOR.

            a.    The Company shall notify the Investor in writing of the
information the Company reasonably requires from the Investor in connection with
any registration statement hereunder. The Investor shall furnish to the Company
such information regarding itself, the Registrable Securities held by it and the
intended method of disposition of the Registrable Securities held by it as shall
be reasonably required to effect the registration of such Registrable Securities
and shall execute such documents in connection with such registration as the
Company may reasonably request.

            b.    The Investor agrees to cooperate with the Company as
reasonably requested by the Company in connection with the preparation and
filing of any registration statement hereunder.

            c.    The Investor agrees that, upon receipt of any notice from the
Company of the happening of any event or existence of facts of the kind
described in Section 3(f) or the first sentence of 3(e), the Investor will
immediately discontinue disposition of Registrable Securities pursuant to any
registration statement(s) covering such Registrable Securities until the
Investor's receipt of the copies of the supplemented or amended prospectus
contemplated by Section 3(f) or the first sentence of 3(e). Notwithstanding
anything to the contrary, the Company shall cause its transfer agent to promptly
deliver shares of Common Stock without any restrictive legend in accordance with
the terms of the Purchase Agreement in connection with any sale of Registrable
Securities with respect to which an Investor has entered into a contract for
sale prior to the Investor's receipt of a notice from the Company of the
happening of any event of the kind described in Section 3(f) or the first
sentence of 3(e) and for which the Investor has not yet settled.

      5.    EXPENSES OF REGISTRATION.

            All reasonable expenses, other than sales or brokerage commissions,
incurred in connection with registrations, filings or qualifications pursuant to
Sections 2 and 3, including, without limitation, all registration, listing and
qualifications fees, printers and accounting fees, and fees and disbursements of
counsel for the Company, shall be paid by the Company.

      6.    INDEMNIFICATION.

            a.    To the fullest extent permitted by law, the Company will, and
hereby does, indemnify, hold harmless and defend the Investor, each Person, if
any, who controls the Investor, the members, the directors, officers, partners,
employees, agents, representatives of the Investor and each Person, if any, who
controls the Investor within the meaning of the 1933 Act or the Securities
Exchange Act of 1934, as amended (the "1934 ACT") (each, an "INDEMNIFIED
PERSON"), against any losses, claims, damages, liabilities, judgments, fines,
penalties, charges, costs, attorneys' fees, amounts paid in settlement or
expenses, joint or several, (collectively, "CLAIMS") incurred in investigating,
preparing or defending any

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action, claim, suit, inquiry, proceeding, investigation or appeal taken from the
foregoing by or before any court or governmental, administrative or other
regulatory agency, body or the SEC, whether pending or threatened, whether or
not an indemnified party is or may be a party thereto ("INDEMNIFIED DAMAGES"),
to which any of them may become subject insofar as such Claims (or actions or
proceedings, whether commenced or threatened, in respect thereof) arise out of
or are based upon: (i) any untrue statement or alleged untrue statement of a
material fact in the Registration Statement, any New Registration Statement or
any post-effective amendment thereto or in any filing made in connection with
the qualification of the offering under the securities or other "blue sky" laws
of any jurisdiction in which Registrable Securities are offered ("BLUE SKY
FILING"), or the omission or alleged omission to state a material fact required
to be stated therein or necessary to make the statements therein not misleading,
(ii) any untrue statement or alleged untrue statement of a material fact
contained in the final prospectus (as amended or supplemented, if the Company
files any amendment thereof or supplement thereto with the SEC) or the omission
or alleged omission to state therein any material fact necessary to make the
statements made therein, in light of the circumstances under which the
statements therein were made, not misleading, (iii) any violation or alleged
violation by the Company of the 1933 Act, the 1934 Act, any other law,
including, without limitation, any state securities law, or any rule or
regulation thereunder relating to the offer or sale of the Registrable
Securities pursuant to the Registration Statement or any New Registration
Statement or (iv) any material violation by the Company of this Agreement (the
matters in the foregoing clauses (i) through (iv) being, collectively,
"VIOLATIONS"). The Company shall reimburse each Indemnified Person promptly as
such expenses are incurred and are due and payable, for any legal fees or other
reasonable expenses incurred by them in connection with investigating or
defending any such Claim. Notwithstanding anything to the contrary contained
herein, the indemnification agreement contained in this Section 6(a): (i) shall
not apply to a Claim by an Indemnified Person arising out of or based upon a
Violation which occurs in reliance upon and in conformity with information
furnished in writing to the Company by such Indemnified Person expressly for use
in connection with the preparation of the Registration Statement, any New
Registration Statement or any such amendment thereof or supplement thereto, if
such prospectus was timely made available by the Company pursuant to Section
3(c) or Section 3(e); (ii) with respect to any superceded prospectus, shall not
inure to the benefit of any such person from whom the person asserting any such
Claim purchased the Registrable Securities that are the subject thereof (or to
the benefit of any person controlling such person) if the untrue statement or
omission of material fact contained in the superceded prospectus was corrected
in the revised prospectus, as then amended or supplemented, if such revised
prospectus was timely made available by the Company pursuant to Section 3(c) or
Section 3(e), and the Indemnified Person was promptly advised in writing not to
use the incorrect prospectus prior to the use giving rise to a violation and
such Indemnified Person, notwithstanding such advice, used it; (iii) shall not
be available to the extent such Claim is based on a failure of the Investor to
deliver or to cause to be delivered the prospectus made available by the
Company, if such prospectus was timely made available by the Company pursuant to
Section 3(c) or Section 3(e); and (iv) shall not apply to amounts paid in
settlement of any Claim if such settlement is effected without the prior written
consent of the Company, which consent shall not be unreasonably withheld. Such
indemnity shall remain in full force and effect regardless of any investigation
made by or on behalf of the Indemnified Person and shall survive the transfer of
the Registrable Securities by the Investor pursuant to Section 9.

            b.    In connection with the Registration Statement or any New
Registration Statement, the Investor agrees to severally and not jointly
indemnify, hold harmless and defend, to the same extent and in the same manner
as is set forth in Section 6(a), the Company, each of its directors, each of its
officers who signs the Registration Statement or any New Registration Statement,
each Person, if any, who controls the Company within the meaning of the 1933 Act
or the 1934 Act (collectively and together with an Indemnified Person, an
"INDEMNIFIED PARTY"), against any Claim or Indemnified Damages to which any of
them may become subject, under the 1933 Act, the 1934 Act or otherwise, insofar
as such Claim or

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Indemnified Damages arise out of or are based upon any Violation, in each case
to the extent, and only to the extent, that such Violation occurs in reliance
upon and in conformity with written information about the Investor set forth on
Exhibit B attached hereto and furnished to the Company by the Investor expressly
for use in connection with such registration statement; and, subject to Section
6(d), the Investor will reimburse any legal or other expenses reasonably
incurred by them in connection with investigating or defending any such Claim;
provided, however, that the indemnity agreement contained in this Section 6(b)
and the agreement with respect to contribution contained in Section 7 shall not
apply to amounts paid in settlement of any Claim if such settlement is effected
without the prior written consent of the Investor, which consent shall not be
unreasonably withheld; provided, further, however, that the Investor shall be
liable under this Section 6(b) for only that amount of a Claim or Indemnified
Damages as does not exceed the net proceeds to the Investor as a result of the
sale of Registrable Securities pursuant to such registration statement. Such
indemnity shall remain in full force and effect regardless of any investigation
made by or on behalf of such Indemnified Party and shall survive the transfer of
the Registrable Securities by the Investor pursuant to Section 9.

            c.    Promptly after receipt by an Indemnified Person or Indemnified
Party under this Section 6 of notice of the commencement of any action or
proceeding (including any governmental action or proceeding) involving a Claim,
such Indemnified Person or Indemnified Party shall, if a Claim in respect
thereof is to be made against any indemnifying party under this Section 6,
deliver to the indemnifying party a written notice of the commencement thereof,
and the indemnifying party shall have the right to participate in, and, to the
extent the indemnifying party so desires, jointly with any other indemnifying
party similarly noticed, to assume control of the defense thereof with counsel
mutually satisfactory to the indemnifying party and the Indemnified Person or
the Indemnified Party, as the case may be; provided, however, that an
Indemnified Person or Indemnified Party shall have the right to retain its own
counsel with the fees and expenses to be paid by the indemnifying party, if, in
the reasonable opinion of counsel retained by the indemnifying party, the
representation by such counsel of the Indemnified Person or Indemnified Party
and the indemnifying party would be inappropriate due to actual or potential
differing interests between such Indemnified Person or Indemnified Party and any
other party represented by such counsel in such proceeding. The Indemnified
Party or Indemnified Person shall cooperate fully with the indemnifying party in
connection with any negotiation or defense of any such action or claim by the
indemnifying party and shall furnish to the indemnifying party all information
reasonably available to the Indemnified Party or Indemnified Person which
relates to such action or claim. The indemnifying party shall keep the
Indemnified Party or Indemnified Person fully apprised at all times as to the
status of the defense or any settlement negotiations with respect thereto. No
indemnifying party shall be liable for any settlement of any action, claim or
proceeding effected without its written consent, provided, however, that the
indemnifying party shall not unreasonably withhold, delay or condition its
consent. No indemnifying party shall, without the consent of the Indemnified
Party or Indemnified Person, consent to entry of any judgment or enter into any
settlement or other compromise which does not include as an unconditional term
thereof the giving by the claimant or plaintiff to such Indemnified Party or
Indemnified Person of a release from all liability in respect to such claim or
litigation. Following indemnification as provided for hereunder, the
indemnifying party shall be subrogated to all rights of the Indemnified Party or
Indemnified Person with respect to all third parties, firms or corporations
relating to the matter for which indemnification has been made. The failure to
deliver written notice to the indemnifying party within a reasonable time of the
commencement of any such action shall not relieve such indemnifying party of any
liability to the Indemnified Person or Indemnified Party under this Section 6,
except to the extent that the indemnifying party is prejudiced in its ability to
defend such action.

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            d.    The indemnification required by this Section 6 shall be made
by periodic payments of the amount thereof during the course of the
investigation or defense, as and when bills are received or Indemnified Damages
are incurred.

            e.    The indemnity agreements contained herein shall be in addition
to (i) any cause of action or similar right of the Indemnified Party or
Indemnified Person against the indemnifying party or others, and (ii) any
liabilities the indemnifying party may be subject to pursuant to the law.

      7.    CONTRIBUTION.

            To the extent any indemnification by an indemnifying party is
prohibited or limited by law, the indemnifying party agrees to make the maximum
contribution with respect to any amounts for which it would otherwise be liable
under Section 6 to the fullest extent permitted by law; provided, however, that:
(i) no seller of Registrable Securities guilty of fraudulent misrepresentation
(within the meaning of Section 11(f) of the 1933 Act) shall be entitled to
contribution from any seller of Registrable Securities who was not guilty of
fraudulent misrepresentation; and (ii) contribution by any seller of Registrable
Securities shall be limited in amount to the net amount of proceeds received by
such seller from the sale of such Registrable Securities.

      8.    REPORTS AND DISCLOSURE UNDER THE SECURITIES ACTS.

            With a view to making available to the Investor the benefits of Rule
144 promulgated under the 1933 Act or any other similar rule or regulation of
the SEC that may at any time permit the Investor to sell securities of the
Company to the public without registration ("RULE 144"), the Company agrees to:

            a.    make and keep public information available, as those terms are
understood and defined in Rule 144;

            b.    file with the SEC in a timely manner all reports and other
documents required of the Company under the 1933 Act and the 1934 Act so long as
the Company remains subject to such requirements and the filing of such reports
and other documents is required for the applicable provisions of Rule 144; and

            c.    furnish to the Investor so long as the Investor owns
Registrable Securities, promptly upon request, (i) a written statement by the
Company that it has complied with the reporting and or disclosure provisions of
Rule 144, the 1933 Act and the 1934 Act, (ii) a copy of the most recent annual
or quarterly report of the Company and such other reports and documents so filed
by the Company, and (iii) such other information as may be reasonably requested
to permit the Investor to sell such securities pursuant to Rule 144 without
registration.

      9.    ASSIGNMENT OF REGISTRATION RIGHTS.

            The Company shall not assign this Agreement or any rights or
obligations hereunder without the prior written consent of the Investor,
including by merger or consolidation. The Investor may not assign its rights
under this Agreement without the written consent of the Company, other than to
an affiliate of the Investor controlled by Steven G. Martin or Joshua B.
Scheinfeld.

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      10.   AMENDMENT OF REGISTRATION RIGHTS.

            Provisions of this Agreement may be amended and the observance
thereof may be waived (either generally or in a particular instance and either
retroactively or prospectively), only with the written consent of the Company
and the Investor.

      11.   MISCELLANEOUS.

            a.    A Person is deemed to be a holder of Registrable Securities
whenever such Person owns or is deemed to own of record such Registrable
Securities. If the Company receives conflicting instructions, notices or
elections from two or more Persons with respect to the same Registrable
Securities, the Company shall act upon the basis of instructions, notice or
election received from the registered owner of such Registrable Securities.

            b.    Any notices, consents, waivers or other communications
required or permitted to be given under the terms of this Agreement must be in
writing and will be deemed to have been delivered: (i) upon receipt, when
delivered personally; (ii) upon receipt, when sent by facsimile (provided
confirmation of transmission is mechanically or electronically generated and
kept on file by the sending party); or (iii) one (1) Trading Day after deposit
with a nationally recognized overnight delivery service, in each case properly
addressed to the party to receive the same. The addresses and facsimile numbers
for such communications shall be:

      If to the Company:
            Probex Corp.
            15510 Wright Brothers Drive
            Addison, TX 75001
            Telephone:  972-788-4772
            Facsimile:  972-980-7068
            Attention:  _________

      With a copy to:
            __________
            __________
            __________
            Telephone:  _________
            Facsimile:  _________
            Attention:  _________

      If to the Investor:
            Fusion Capital Fund II, LLC
            222 Merchandise Mart Plaza, Suite 9-112
            Chicago, IL 60654
            Telephone:  312-644-6644
            Facsimile:  312-644-6244
            Attention:  Steven G.  Martin

or at such other address and/or facsimile number and/or to the attention of such
other person as the recipient party has specified by written notice given to
each other party three (3) Trading Days prior to the effectiveness of such
change. Written confirmation of receipt (A) given by the recipient of such
notice,

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consent, waiver or other communication, (B) mechanically or electronically
generated by the sender's facsimile machine containing the time, date, recipient
facsimile number and an image of the first page of such transmission or (C)
provided by a nationally recognized overnight delivery service, shall be
rebuttable evidence of personal service, receipt by facsimile or receipt from a
nationally recognized overnight delivery service in accordance with clause (i),
(ii) or (iii) above, respectively.

            c.    Failure of any party to exercise any right or remedy under
this Agreement or otherwise, or delay by a party in exercising such right or
remedy, shall not operate as a waiver thereof.

            d.    The corporate laws of the State of Delaware shall govern all
issues concerning the relative rights of the Company and its stockholders. All
other questions concerning the construction, validity, enforcement and
interpretation of this Agreement shall be governed by the internal laws of the
State of Illinois, without giving effect to any choice of law or conflict of law
provision or rule (whether of the State of Illinois or any other jurisdictions)
that would cause the application of the laws of any jurisdictions other than the
State of Illinois. Each party hereby irrevocably submits to the exclusive
jurisdiction of the state and federal courts sitting the City of Chicago, for
the adjudication of any dispute hereunder or in connection herewith or with any
transaction contemplated hereby or discussed herein, and hereby irrevocably
waives, and agrees not to assert in any suit, action or proceeding, any claim
that it is not personally subject to the jurisdiction of any such court, that
such suit, action or proceeding is brought in an inconvenient forum or that the
venue of such suit, action or proceeding is improper. Each party hereby
irrevocably waives personal service of process and consents to process being
served in any such suit, action or proceeding by mailing a copy thereof to such
party at the address for such notices to it under this Agreement and agrees that
such service shall constitute good and sufficient service of process and notice
thereof. Nothing contained herein shall be deemed to limit in any way any right
to serve process in any manner permitted by law. If any provision of this
Agreement shall be invalid or unenforceable in any jurisdiction, such invalidity
or unenforceability shall not affect the validity or enforceability of the
remainder of this Agreement in that jurisdiction or the validity or
enforceability of any provision of this Agreement in any other jurisdiction.
EACH PARTY HEREBY IRREVOCABLY WAIVES ANY RIGHT IT MAY HAVE, AND AGREES NOT TO
REQUEST, A JURY TRIAL FOR THE ADJUDICATION OF ANY DISPUTE HEREUNDER OR IN
CONNECTION HEREWITH OR ARISING OUT OF THIS AGREEMENT OR ANY TRANSACTION
CONTEMPLATED HEREBY.

            e.    This Agreement, and the Purchase Agreement constitute the
entire agreement among the parties hereto with respect to the subject matter
hereof and thereof. There are no restrictions, promises, warranties or
undertakings, other than those set forth or referred to herein and therein. This
Agreement and the Purchase Agreement supersede all prior agreements and
understandings among the parties hereto with respect to the subject matter
hereof and thereof.

            f.    Subject to the requirements of Section 9, this Agreement shall
inure to the benefit of and be binding upon the permitted successors and assigns
of each of the parties hereto.

            g.    The headings in this Agreement are for convenience of
reference only and shall not limit or otherwise affect the meaning hereof.

            h.    This Agreement may be executed in identical counterparts, each
of which shall be deemed an original but all of which shall constitute one and
the same agreement. This Agreement, once executed by a party, may be delivered
to the other party hereto by facsimile transmission of a copy of this Agreement
bearing the signature of the party so delivering this Agreement.

                                       10
<PAGE>
            i.    Each party shall do and perform, or cause to be done and
performed, all such further acts and things, and shall execute and deliver all
such other agreements, certificates, instruments and documents, as the other
party may reasonably request in order to carry out the intent and accomplish the
purposes of this Agreement and the consummation of the transactions contemplated
hereby.

            j.    The language used in this Agreement will be deemed to be the
language chosen by the parties to express their mutual intent and no rules of
strict construction will be applied against any party.

            k.    This Agreement is intended for the benefit of the parties
hereto and their respective permitted successors and assigns, and is not for the
benefit of, nor may any provision hereof be enforced by, any other Person.

                                   * * * * * *

                                       11
<PAGE>
      IN WITNESS WHEREOF, the parties have caused this Registration Rights
Agreement to be duly executed as of day and year first above written.

                                    THE COMPANY:

                                    PROBEX CORP.

                                    By:______________________
                                    Name:
                                    Title:

                                    BUYER:

                                    FUSION CAPITAL FUND II, LLC
                                    BY: FUSION CAPITAL PARTNERS, LLC
                                    BY: SGM HOLDINGS CORP.

                                    By:_______________________
                                    Name: Steven G. Martin
                                    Title: President

                                       12
<PAGE>
                                    EXHIBIT A

                        TO REGISTRATION RIGHTS AGREEMENT

                         FORM OF NOTICE OF EFFECTIVENESS
                            OF REGISTRATION STATEMENT

[Date]

[TRANSFER AGENT]
___________________
___________________

Re: [__________]

Ladies and Gentlemen:

       We are counsel to Probex Corp., a Delaware corporation (the "COMPANY"),
and have represented the Company in connection with that certain Common Stock
Purchase Agreement, dated as of _______, 2002 (the "PURCHASE AGREEMENT"),
entered into by and between the Company and Fusion Capital Fund II, LLC (the
"BUYER") pursuant to which the Company has agreed to issue to the Holder shares
of the Company's Common Stock, par value $0.001 per share (the "COMMON STOCK"),
in an amount up to Twenty Million Dollars ($20,000,000) (the "PURCHASE SHARES"),
in accordance with the terms of the Purchase Agreement. Pursuant to the Purchase
Agreement, the Company also has entered into a Registration Rights Agreement,
dated as of ______, 2002, with the Buyer (the "REGISTRATION RIGHTS AGREEMENT")
pursuant to which the Company agreed, among other things, to register the
Purchase Shares and the Commitment Shares under the Securities Act of 1933, as
amended (the "1933 Act"). In connection with the Company's obligations under the
Purchase Agreement and the Registration Rights Agreement, on _______, 2002, the
Company filed a Registration Statement (File No. 333-_________) (the
"REGISTRATION STATEMENT") with the Securities and Exchange Commission (the
"SEC") relating to the sale of the Purchase Shares and the Commitment Shares.

       In connection with the foregoing, we advise you that a member of the
SEC's staff has advised us by telephone that the SEC has entered an order
declaring the Registration Statement effective under the 1933 Act at 5:00 P.M.
on __________, 2002 and we have no knowledge, after telephonic inquiry of a
member of the SEC's staff, that any stop order suspending its effectiveness has
been issued or that any proceedings for that purpose are pending before, or
threatened by, the SEC and the Purchase Shares, and the Commitment Shares are
available for sale under the 1933 Act pursuant to the Registration Statement.

       The Buyer has confirmed it shall comply with all securities laws and
regulations applicable to it including applicable prospectus delivery
requirements upon sale of the Purchase Shares and the Commitment Shares.

                                    Very truly yours,
                                    [Company Counsel]
                                    By:____________________

CC:    Fusion Capital Fund II, LLC
<PAGE>
                                    EXHIBIT B

                        TO REGISTRATION RIGHTS AGREEMENT

     INFORMATION ABOUT THE INVESTOR FURNISHED TO THE COMPANY BY THE INVESTOR
         EXPRESSLY FOR USE IN CONNECTION WITH THE REGISTRATION STATEMENT<PAGE>
                                                                   EXHIBIT 10.40

                                  PAT HAGGERTY

                NORTH TEXAS COMMERCIAL ASSOCIATION OF REALTORS(R)

                           COMMERCIAL LEASE AGREEMENT

TABLE OF CONTENTS

<TABLE>
<CAPTION>
Article                                                                     Page
<S>                                                                         <C>
1.  Defined Terms                                                              1
2.  Lease and Lease Term                                                       2
3.  Rent and Security Deposit                                                  2
4.  Taxes                                                                      3
5.  Insurance and Indemnity                                                    3
6.  Use of Demised Premises                                                    4
7.  Property Condition, Maintenance, Repairs and Alterations                   5
8.  Damage or Destruction                                                      6
9.  Condemnation                                                               7
10. Assignment and Subletting                                                  7
11. Default and Remedies                                                       7
12. landlord's Contractual Lien                                                9
13. Protection of Lenders                                                      9
14. Environmental Representations and Indemnity                               10
15. Professional Service Fees                                                 10
16. Miscellaneous                                                             11
17. Additional Provisions                                                     13
</TABLE>

EXHIBITS AND ADDENDA. Any exhibit or addendum attached to this Lease is
incorporated as a part of this Lease for all purposes. Any term not specifically
defined in the Addenda shall have the same meaning given to it in the body of
this Lease. To the extent any provisions in the body of this Lease conflict with
the Addenda, the Addenda shall control.

[CHECK ALL BOXES WHICH APPLY. BOXES NOT CHECKED DO NOT APPLY.]

[X] Exhibit A    Survey and/or Legal Description of the Property
[X] Exhibit B    Floor plan and/or Site Plan

[X] Addendum A   Expense Reimbursement
[X] Addendum B   Renewal Options
[ ] Addendum C   Right of First Refusal for Additional Space
[ ] Addendum D   Percentage Rental/Gross Sales Reports
[ ] Addendum E   Guarantee
[ ] Addendum F   Construction of Improvements
[ ] Addendum G   Rules and Regulations
[X] Addendum H   Other Additional Provisions

IN CONSIDERATION of the terms, provisions and agreements contained in this
Lease, the parties agree as follows:

ARTICLE ONE: DEFINED TERMS. As used in this Commercial Lease Agreement (the
"Lease"), the terms set forth in this Article One have the following respective
meanings:

1.01.  EFFECTIVE DATE: The last date beneath the signatures of Landlord and
       Tenant on page 13 below.

1.02.  LANDLORD: Tom Taylor, Arch Jacobson, and Estate of James A. Moran
       ADDRESS:  6516 Forest Park Road
                 Dallas Texas 75235  Telephone: 214-358-0174  Fax: 214-358-0445
1.03.  TENANT:   Probex Corp.
       ADDRESS:  13355 Noel Rd. Suite 1200
                 Dallas TX 75240     Telephone: 972-788-4772  Fax: 972-980-7068

1.04.  DEMISED PREMISES:________________________________________________________

       A.   STREET ADDRESS:  15510 Wright Brothers Drive, Addison Texas  75001
            in  Dallas  County, Texas.

       B.   LEGAL DESCRIPTION: The property on which the Demised Premises is
            situated (the "Property") is more particularly described as: Lot 9,
            in Block A of the Addison Airport Industrial District an Addition to
            the Town of Addison, Texas according to the map recorded in Volume
            50, Page 207 of the Map records of Dallas County or is described on
            EXHIBIT A, SURVEY AND/OR LEGAL DESCRIPTION.

      C.    FLOOR PLAN OR SITE PLAN: Being a floor area of approximately 21,290
            square feet and being approximately _____ feet by _____ feet
            (measured to the exterior of outside walls and to the center of the
            interior walls) and being more particularly shown in outline form on
            EXHIBIT B, FLOOR PLAN AND/OR SITE PLAN.

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<PAGE>
       D.   Tenant's pro rata share of the Property is 100%. [See ADDENDUM A,
            EXPENSE REIMBURSEMENT, if applicable.]

1.05.  LEASE TERM: Five years and 0 months beginning on June 1, 2002 (the
       "Commencement Date") and ending on May 31, 2007 (the "Expiration Date").

1.06.  BASE RENT: $479,024.82 total Base Rent for the Lease Term payable in
       monthly installments of $8,870.83 per month in advance. (The total amount
       of Rent is defined in Section 3.01.)

1.07.  PERCENTAGE RENTAL RATE: N/A%. [See ADDENDUM D, PERCENTAGE RENTAL/GROSS
       SALES REPORTS, if applicable]

1.08.  SECURITY DEPOSIT: $8,870.83 (due upon execution of this Lease). [See
       Section 3.04]

1.09.  PERMITTED USE: __________________________________________________ for
       tenant's business in accordance with the Town of Addison, Addison
       Airport, and Texas regulations. [See Section 6.01]

1.10.  Party to whom Tenant is to deliver payments under this Lease [check one]:
       [X] Landlord, [ ] Principal Broker, or [ ] Other ________________________
       Landlord may designate in writing the party authorized to act on behalf
       of Landlord to enforce this Lease. Any such authorization will remain
       in effect until it is revoked by Landlord in writing.

1.11.  PRINCIPAL BROKER: Patrick J. Haggerty (2%), acting as [CHECK ONE]:
       [X] agent for Landlord exclusively, [ ] agent for Tenant exclusively,
       [ ] an intermediary. Principal Broker's Address: 16475 Dallas Parkway,
       Addison, Texas 7500 TELEPHONE: (___) __________ FAX: (___) __________

1.12.  COOPERATING BROKER: Miller Commercial (4%), acting as [CHECK ONE]:
       [ ] agent for Landlord exclusively, [X] agent for Tenant exclusively,
       [ ] an intermediary. Cooperating Broker's Address: 5001 Spring Valley,
       Suite 1150, Dallas, Texas 75244  TELEPHONE: (972) 419-4000
       FAX: (972) __________

1.13.  THE FEE: The Professional Service Fee shall be as set forth in [CHECK
       ONE]: [ ] Paragraph A, or [X] Paragraph B of Section 15.01.

       A.  The percentage applicable for leases in Sections 15.01 and 15.03
           shall be six percent (6%).

       B.  The percentage applicable in Section 15.04 in the event of a sale
           shall be six percent (6%).

1.14.  ACCEPTANCE: The number of days for acceptance of this offer is _____
       days. [See Section 16.14]

ARTICLE TWO: LEASE AND LEASE TERM. (SEE Addendum H, SECTION A)

2.01. LEASE OF DEMISED PREMISES FOR LEASE TERM. Landlord leases the Demised
Premises to Tenant and Tenant leases the Demised Premises from Landlord for the
Lease Term stated in Section 1.05. The Commencement Date is the date specified
in Section 1.05, unless advanced or delayed under any provision of this Lease.

2.02. DELAY IN COMMENCEMENT. Landlord shall not be liable to Tenant if Landlord
does not deliver possession of the Demised Premises to Tenant on the
Commencement Date specified in Section 1.05 above. Landlord's non-delivery of
possession of the Demised Premises to Tenant on the Commencement Date will not
affect this Lease or the obligations of Tenant under this Lease. However, the
Commencement Date shall be delayed until possession of the Demised Premises is
delivered to Tenant. The Lease Term shall be extended for a period equal to the
delay in delivery of possession of the Demised Premises to Tenant, plus the
number of days necessary for the Lease Term to expire on the last day of a
month. If Landlord does not deliver possession of the Demised Premises to Tenant
within sixty (60) days after the Commencement Date specified in Section 1.05,
Tenant may cancel this Lease by giving written notice to Landlord within ten
(10) days after the 60-day period ends. If Tenant gives such notice, this Lease
shall be canceled effective as of the date of its execution, and no party shall
have any obligations under this Lease. If Tenant does not give such notice
within the time specified,

(C) Copyright 1996 NTCAR form 02 (1/96)                                   Page 2
<PAGE>
Tenant shall have no right to cancel this Lease, and the Lease Term shall
commence upon the delivery of possession of the Demised Premises to Tenant. If
delivery of possession of the Demised Premises to Tenant is delayed, Landlord
and Tenant shall, upon such delivery, execute on amendment to this Lease setting
forth the revised Commencement Date and Expiration Date of the Lease Term.

2.03. EARLY OCCUPANCY. If Tenant occupies the Demised Premises prior to the
Commencement Date, Tenant's occupancy of the Demised Premises shall be subject
to all of the provisions of this Lease. Early occupancy of the Demised Premises
shall not advance the Expiration Date. Unless otherwise provided herein, Tenant
shall pay Base Rent and all other charges specified in this Lease for the period
of occupancy.

2.04. HOLDING OVER. Tenant shall vacate the Demised Premises immediately upon
the expiration of the Lease Term or earlier termination of this Lease. Tenant
shall reimburse Landlord for and indemnify Landlord against all actual damages
incurred by Landlord as a result of any delay by Tenant in vacating the Demised
Premises. If Tenant does not vacate the Demised Premises upon the expiration of
the Lease Term or earlier termination of this Lease, Tenant's occupancy of the
Demised Premises shall be a day-to-day tenancy, subject to all of the terms of
this Lease, except that the Base Rent during the holdover period shall be
increased to an amount which is one-and-one-half (1-1/2) times the Base Rent in
effect on the expiration or termination of this Lease, computed on a daily basis
for each day of the holdover period, plus all additional sums due under this
Lease. This paragraph shall not be construed as Landlord's consent for Tenant to
hold over or to extend this Lease.

ARTICLE THREE: RENT AND SECURITY DEPOSIT

3.01. MANNER OF PAYMENT. All sums payable under this Lease by Tenant (the
"Rent") shall be made to the Landlord at the address designated in Section 1.02,
unless another person is designated in Section 1.10, or to any other party or
address as Landlord may designate in writing. Any and all payments made to a
designated third party for the account of the Landlord shall be deemed made to
Landlord when received by the designated third party. All sums payable by Tenant
under this Lease, whether or not expressly denominated as rent, shall constitute
rent for the purposes of Section 502(b)(6) of the Bankruptcy Code and for all
other purposes. The Base Rent is the minimum rent for the Demised Premises and
is subject to the terms and conditions contained in this Lease, together with
the attached Addenda, if any.

3.02. TIME OF PAYMENT. Upon execution of this Lease, Tenant shall pay the
installment of Base Rent for the first month of the Lease Term. On or before the
first day of the second month of the Lease Term and of each month thereafter,
the installment of Base Rent and other sums due under this Lease shall be due
and payable, in advance, without off-set, deduction or prior demand. Tenant
shall cause payments to be properly mailed or otherwise delivered so as to be
actually received by the party identified in 1.10 above on or before the due
date (and not merely deposited in the mail). If the Lease Term commences or ends
on a day other than the first or last day of a calendar month, the rent for any
fractional calendar month following the Commencement Date or preceding the end
of the Lease Term shall be prorated by days.

3.03. LATE CHARGES. Tenant's failure to promptly pay sums due under this Lease
may cause Landlord to incur unanticipated costs. The exact amount of those costs
is impractical or extremely difficult to ascertain. The costs may include, but
are not limited to, processing and accounting charges and late charges which may
be imposed on Landlord by any ground lease or deed of trust encumbering the
Demised Premises. Payments due to Landlord under this Lease are not an extension
of credit subject to any __________ or periods set forth herein. Therefore, if
any payment under the Lease is not actually received on or before the due date
(and not merely deposited in the mail), Landlord may, at Landlord's option and
to the extent allowed by applicable law, impose a Late Charge on any late
payments in an amount equal to one-half of one percent (0.5%) of the amount of
the past due payment (the "Late Charge") per day for each day after the due
date, until the past due amount in Good Funds is received by Landlord, up to a
maximum of ten percent (10%) of the past due amount. A Late Charge may be
imposed only once on each past due payment. Any Late Charge will be in addition
to Landlord's other remedies for nonpayment of rent. If any check tendered to
Landlord by Tenant under this Lease is dishonored for any reason, Tenant shall
pay to the party receiving payments under this Lease a fee of twenty-five
dollars ($25.00), plus (at Landlord's option) a Late Charge as provided above
until good funds are received by Landlord. The parties agree that any Late
Charge and dishonored check fee represent a fair and reasonable estimate of the
costs Landlord will incur by reason of the late payment or dishonored check.
Payments received from Tenant shall be applied first to any Late Charges, second
to Base Rent, and last to other unpaid charges or reimbursements due to
Landlord. Notwithstanding the foregoing, Landlord will not impose a Late Charge
as to the first late payment in any calendar year, unless Tenant fails to pay
the late payment to Landlord within five (5) business days after the delivery of
a written notice from Landlord to Tenant demanding the late payment be paid.
However, Landlord may impose a Late Charge without advance notice to Tenant on
any subsequent late payment in the same calendar year.

(C) Copyright 1996 NTCAR form 02 (1/96)                                   Page 3
<PAGE>
3.04. SECURITY DEPOSIT. Upon execution of this Lease, Tenant shall deposit with
Landlord a cash Security Deposit in the amount stated in Section 1.08. Landlord
may apply all or part of the Security Deposit to any unpaid Rent or other
charges due from Tenant or to cure any other defaults of Tenant. If Landlord
properly uses any part of the Security Deposit, Tenant shall restore the
Security Deposit to its full amount within ten (10) days after Landlord's
written demand. Tenant's failure to restore the full amount of the Security
Deposit within the time specified shall be a default under this Lease. No
interest will be paid on the Security Deposit. Landlord will not be required to
keep the Security Deposit separate from its other accounts and no trust
relationship is created with respect to the Security Deposit. Upon any
termination of this Lease not resulting from Tenant's default, and after Tenant
has vacated the Property and cleaned and restored the Demised Premises in the
manner required by this Lease, Landlord shall refund the unused portion of the
Security Deposit to Tenant within thirty days after the Termination Date or
thirty days after Tenant fully complies with the conditions of termination as
required in Section 7.05, whichever is later.

3.05. GOOD FUNDS PAYMENTS. If, for any reason whatsoever, any two or more
payments by check from Tenant to Landlord for Rent are dishonored and returned
unpaid, thereafter Landlord may, at Landlord's sole option, upon written notice
to Tenant, require that all future payments of Rent for the remaining term of
the Lease must be made by cash, certified check, cashier's check, or money order
("Good Funds") and that the delivery of Tenant's personal or corporate check
will no longer constitute payment of Rent under this Lease. Any acceptance by
Landlord of a payment for Rent by Tenant's personal or corporate check
thereafter shall not be construed as a waiver of Landlord's right to insist upon
payment by Good Funds as set forth herein.

ARTICLE FOUR: TAXES

4.01. PAYMENT BY LANDLORD. Landlord shall pay the real estate taxes on the
Demised Premises during the Lease Term.

4.02. IMPROVEMENTS BY TENANT. If the real estate taxes levied against the
Demised Premises for the real estate tax year in which the Lease Term commences
are increased solely as a result of any alterations, additions or improvements
made by Tenant or by Landlord at the request of Tenant, Tenant shall pay to
Landlord upon demand the amount of the increase and continue to pay the increase
during the Lease Term. Landlord shall use reasonable efforts to obtain from the
tax assessor or assessors a written statement of the total amount of the
increase and provide same to tenant.

4.03. JOINT ASSESSMENT. If the real estate taxes are assessed against the
Demised Premises jointly with other property not constituting a part of the
Demised Premises, the real estate taxes applicable to the Demised Premises shall
be equal to the amount bearing the same proportion to the aggregate assessment
that the total square feet of building area in the Demised Premises bears to the
total square feet of building area included in the joint assessment.

4.04. PERSONAL PROPERTY TAXES. Tenant shall pay all taxes assessed against trade
fixtures, furnishings, equipment, inventory, products, or any other personal
property belonging to Tenant. Tenant shall use reasonable effort to have
Tenant's property taxed separately from the Demised Premises. If any of Tenant's
property is taxed with the Demised Premises, Tenant shall pay the taxes for its
property to Landlord within fifteen (15) days after Tenant receives a written
statement from Landlord for the property taxes.

ARTICLE FIVE: INSURANCE AND INDEMNITY

5.01. CASUALTY INSURANCE. During the Lease Term, Landlord shall maintain
policies of insurance covering loss of or damage to the Demised Premises in an
amount or percentage of replacement value as Landlord deems reasonable in
relation to the age, location, type of construction and physical condition of
the Demised Premises and the availability of insurance at reasonable rates. The
policies shall provide protection against all perils included within the
classification of fire and extended coverage and any other perils which Landlord
deems necessary. Landlord may, at Landlord's option and cost and expense, obtain
insurance coverage for Tenant's fixtures, equipment or building improvements
installed by Tenant in or on the Demised Premises. Tenant shall, at Tenant's
expense, maintain insurance on its fixtures, equipment and building improvements
as Tenant deems necessary to protect Tenant's interest. Tenant shall not do or
permit to be done anything which invalidates any insurance policies. Any
casualty insurance carried by Landlord or Tenant shall be for the sole benefit
of the party carrying the insurance and under its sole control.

5.02. INCREASE IN PREMIUMS. Tenant shall not permit any operation or activity to
be conducted, or storage or use of any volatile or any other materials, on or
about the Demised Premises that would cause suspension or cancellation of any
fire and extended coverage insurance policy carried by Landlord, or increase the
premiums therefor, without the prior written consent of Landlord. If Tenant's
use and occupancy of the Demised Premises causes an increase in the premiums for
any

(C) Copyright 1996 NTCAR form 02 (1/96)                                   Page 4
<PAGE>
fire and extended coverage insurance policy carried by Landlord, Tenant shall
pay to Landlord, as additional rental, the amount of the increase within ten
days after demand and presentation by Landlord of written evidence of the
increase.

5.03. LIABILITY INSURANCE. During the Lease Term, Tenant shall maintain a
commercial general liability policy of insurance, at Tenant's expense, insuring
Landlord against liability arising out of the ownership, use, occupancy, or
maintenance of the Demised Premises. The initial amounts of the insurance must
be at least: $1,000,000 for Each Occurrence, $2,000,000 General Aggregate per
policy year, $100,000 Property Damage for the Demised Premises, and $10,000
Medical Expense; plus a $5,000,000 commercial general liability umbrella; and
shall be subject to periodic increases based upon economic factors as Landlord
may determine, in Landlord's reasonable discretion, exercised in good faith.
However, the amounts of the insurance shall not limit Tenant's liability nor
relieve Tenant of any obligation under this Lease. The policies must contain
cross-liability endorsements, if applicable, and must insure Tenant's
performance of the indemnity provisions of Section 5.04. The policies must
contain a provision which prohibits cancellation or modification of the policy
except upon thirty (30) days' prior written notice to Landlord. Tenant may
discharge Tenant's obligations under this Section by naming Landlord as an
additional insured under a comprehensive policy of commercial general liability
insurance maintained by Tenant and containing the coverage and provisions
described in this Section. Tenant shall deliver a copy of the policy or
certificate (or a renewal) to Landlord prior to the Commencement Date and prior
to the expiration of the policy during the Lease Team. If Tenant fails to
maintain the policy, Landlord may elect to maintain the insurance at Tenant's
expense. Tenant may, at Tenant's expense, maintain other liability insurance as
Tenant deems necessary.

5.04. INDEMNITY. Landlord shall not be liable to Tenant or to Tenant's
employees, agents, invitees or visitors, or to any other person, for any injury
to persons or damage to property on or about the Demised Premises or any
adjacent area owned by Landlord caused by the negligence or misconduct of
Tenant, Tenant's employees, subtenants, agents, licensees or concessionaires or
any other person entering the Demised Premises under express or implied
invitation of Tenant, or arising out of the use of the Demised Premises by
Tenant and the conduct of Tenant's business, or arising out of any breach or
default by Tenant in the performance of Tenant's obligations under this Lease;
and Tenant hereby agrees to indemnify and hold Landlord harmless from any loss,
expense or claims arising out of such damage or injury. Tenant shall not be
liable for any injury or damage caused by the negligence or misconduct of
Landlord, or Landlord's employees or agents, and Landlord agrees to indemnify
and hold Tenant harmless from any loss, expense or damage arising out of such
damage or injury.

5.05. COMPARATIVE NEGLIGENCE. Tenant and Landlord hereby unconditionally and
irrevocably agree to indemnify, defend and hold each other and their officers,
agents, directors, subsidiaries, partners, employees, licensees and counsel
harmless, to the extent of each party's comparative negligence, if any, from and
against any and all loss, liability, demand, damage, judgment, suit, claim,
deficiency, interest, fee, charge, cost or expense (including, without
limitation, interest, court costs and penalties, reasonable attorney's fees and
disbursements and amounts paid in settlement, or liabilities resulting from any
change in federal, state or local law or regulation or interpretation of this
Lease) of whatever nature, on a comparative negligence basis, even when caused
in part by Landlord's or Tenant's negligence or the joint or concurring
negligence of Landlord, Tenant, and any other person or entity, which may result
or to which Landlord or Tenant and/or any of their officers, agents, directors,
employees, subsidiaries, partners, licensees and counsel may sustain, suffer,
incur or become subject to in connection with or arising in any way whatsoever
out of the leasing, operation, promotion, management, maintenance, repair, use
or occupation of the Demised Premises, or any other activity of whatever nature
in connection therewith, or arising out of or by reason of any investigation,
litigation or other proceedings brought or threatened, arising out of or based
upon the leasing, operation, promotion, management, maintenance, repair, use or
occupancy of the Demised Premises, or any other activity on the Demised
Premises. This provision shall survive the expiration or termination of this
Lease.

5.06. WAIVER OF SUBROGATION. Each party to this Lease waives any and every claim
which arises or may arise in its favor against the other party during the term
of this Lease or any renewal or extension of this Lease for any and all loss of,
or damage to, any of its property located within or upon, or constituting a part
of, the Demised Premises, which loss or damage is covered by valid and
collectible fire and extended coverage insurance policies, to the extent that
such loss or damage is recoverable under such insurance policies. These mutual
waivers shall be in addition to, and not in limitation or derogation of, any
other waiver or release contained in this Lease with respect to any loss of, or
damage to, property of the parties. Inasmuch as these mutual waivers will
preclude the assignment of any aforesaid claim by way of subrogation or
otherwise to an insurance company (or any other person), each party hereby
agrees to give immediately to each insurance company (which has issued to such
party policies of fire and extended coverage insurance) written notice of the
terms of such mutual waivers, and to cause such policies to be properly endorsed
to prevent the invalidation of the insurance coverage by reason of these
waivers.

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ARTICLE SIX: USE OF DEMISED PREMISES

6.01. PERMITTED USE. SEE Addendum H, SECTION B. Tenant may use the Demised
Premises only for the Permitted Use stated in Section 1.09. The parties to this
Lease acknowledge that the current use of the Demised Premises or the
improvements located on the Demised Premises, or both, may or may not conform to
the city zoning ordinance with respect to the permitted use, height, setback
requirements, minimum parking requirements, coverage ratio of improvements to
total area of land, and other matters which may have a significant economic
impact upon the Tenant's intended use of the Demised Premises. Tenant
acknowledges that Tenant has or will independently investigate and verify to
Tenant's satisfaction the extent of any limitations or non-conforming uses of
the Demised Premises. Tenant further acknowledges that Tenant is not relying
upon any warranties or representations of Landlord or the Brokers who are
participating in the negotiation of this Lease concerning the Permitted Use of
the Demised Property or with respect to any uses of the improvements located on
the Demised Premises.

6.02. COMPLIANCE WITH LAW. SEE Addendum H, SECTION C. Tenant shall comply with
all governmental laws, ordinances and regulations applicable to the use of the
Demised Premises, and shall promptly comply with all governmental orders and
directives for the correction, prevention and abatement of nuisances and other
activities in or upon, or connected with the Demised Premises, all at Tenant's
sole expense, including any expense or cost resulting from the construction or
installation of fixtures and improvements or other accommodations for
handicapped or disabled persons required for compliance with governmental laws
and regulations, including but not limited to the Texas Architectural Barriers
Act (Article 9102 and any successor statute) and the Americans with Disabilities
Act (the "ADA"). To the extent any alterations to the Demised Premises are
required by the ADA or other applicable laws or regulations, Tenant shall bear
the expense of the alterations. To the extent any alterations to areas of the
Property outside the Demised Premises are required by Title III of the ADA or
other applicable laws or regulations (for "path of travel" requirements or
otherwise), Landlord shall bear the expense of the alterations.

6.03. CERTIFICATE OF OCCUPANCY. If required, Tenant shall obtain a Certificate
of Occupancy from the municipality in which the Property is located prior to
occupancy of the Demised Premises. Tenant may apply for a Certificate of
Occupancy prior to the Commencement Date and, if Tenant is unable to obtain a
Certificate of Occupancy, Tenant shall have the right to terminate this Lease by
written notice to Landlord if Landlord or Tenant is unwilling or unable to cure
the defects which prevented the issuance of the Certificate of Occupancy.
Landlord may, but has no obligation to, cure any such defects, including any
repairs, installations, or replacements of any items which are not presently
existing on the Demised Premises, or which have not been expressly agreed upon
by Landlord in writing.

6.04. SIGNS. Without the prior written consent of Landlord (which consent shall
not be unreasonably withheld), Tenant may not place any signs, ornaments or
other objects upon the Demised Premises or on the Property, including but not
limited to the roof or exterior of the building or other improvements on the
Property, or paint or otherwise decorate or deface the exterior of the building.
Any signs installed by Tenant must conform with applicable laws, deed
restrictions on the Property, and other applicable requirements. Tenant must
remove all signs, decorations and ornaments at the expiration or termination of
this Lease and must repair any damage and close any holes caused by the removal.

6.05. UTILITY SERVICES. Tenant shall pay the cost of all utility services,
including but not limited to initial connection charges, all charges for gas,
water, sewerage, storm water disposal, communications and electricity used on
the Demised Premises, and for replacing all electric lights, lamps and tubes.

6.06. LANDLORD'S ACCESS. Landlord and Landlord's agents shall have the right to,
during normal business hours and upon reasonable advance notice, and without
unreasonably interfering with Tenant's business, enter the Demised Premises: (a)
to inspect the general condition and state of repair of the Demised Premises,
(b) to make repairs required or permitted under this Lease, (c) to show the
Demised Premises or the property to any prospective tenant or purchaser, and (d)
for any other reasonable purpose. If Tenant changes the locks on the Demised
Premises, Tenant must provide Landlord with a copy of each separate key. During
the final one hundred fifty (150) days of the Lease Term, Landlord and
Landlord's agents may erect and maintain on or about the Demised Premises signs
advertising the Demised Premises for lease or for sale.

6.07. POSSESSION. If Tenant pays the rent, properly maintains the Demised
Premises, and complies with all other terms of this Lease, Tenant may occupy and
enjoy the Demised Premises for the full Lease Term, subject to the provisions of
this Lease.

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6.08. EXEMPTIONS FROM LIABILITY. Landlord shall not be liable for any damage or
injury to the persons, business (or any loss of income), goods, inventory,
furnishings, fixtures, equipment, merchandise or other property of Tenant,
Tenant's employees, invitees, customers or any other person in or about the
Demised Premises, whether the damage or injury is caused by or results from: (a)
fire, steam, electricity, water, gas or wind; (b) the breakage, leakage,
obstruction or other defects of pipes, sprinklers, wires, appliances, plumbing,
air conditioning or lighting fixtures or any other cause; (c) conditions arising
on or about the Demised Premises or upon other portions of any building of which
the Demised Premises is a part, or from other sources or places; or (d) any act
or omission of any other tenant of any building on the Property. Landlord shall
not be liable for any damage or injury even though the cause of or the means of
repairing the damage or injury are not accessible to Tenant. The provisions of
this Section 6.08 shall not, however, exempt Landlord from liability for
Landlord's gross negligence or willful misconduct.

ARTICLE SEVEN: PROPERTY CONDITION, MAINTENANCE, REPAIRS AND ALTERATIONS

7.01. PROPERTY CONDITION. Except as disclosed in writing by Landlord to Tenant
contemporaneously with the execution of this Lease, to the best of Landlord's
actual knowledge the Demised Premises has no known latent structural defects,
construction defects of a material nature, and to the best of Landlord's actual
knowledge none of the improvements has been constructed with materials known to
be a potential health hazard to occupants of the Demised Premises. Tenant
acknowledges that neither the Principal Broker nor any Cooperating Broker has
made any warranty or representation to Tenant with respect to the condition of
the Demised Promises, and that Tenant is relying exclusively upon Tenant's own
investigations and the representations of Landlord, if any, with respect to the
condition of the Demised Premises. Landlord and Tenant agree to hold the Brokers
harmless of and from any and all damages, claims, costs and expenses of every
kind and character resulting from or related to Landlord's furnishing to the
Brokers any false, incorrect or inaccurate information with respect to the
Demised Premises, or Landlord's concealing any material information with respect
to the condition of the Demised Premises. Other than as expressly set forth in
this Lease, Landlord represents that on the Commencement Date (and for a period
of thirty (30) days thereafter) the building fixtures and equipment, plumbing
and plumbing fixtures, electrical and lighting system, any fire protection
sprinkler system, ventilating equipment, heating system, air conditioning
equipment, roof, skylights, doors, overhead doors, windows, dock levelers,
elevators, and the interior of the Demised Premises in general are in good
operating condition. Tenant shall have a period of thirty (30) days following
the Commencement Date in which to inspect the Demised Premises and to notify
Landlord in writing of any defects and maintenance, repairs or replacements
required to the above named equipment, fixtures, systems and interior. Within a
reasonable period of time after the timely receipt of any such written notice
from Tenant, Landlord shall, at Landlord's expense, correct the defects and
perform the maintenance, repairs and replacements.

7.02. ACCEPTANCE OF DEMISED PREMISES. Subject to the provisions in Section 7.01,
Tenant acknowledges that: (a) a full and complete inspection of the Demised
Premises and adjacent common areas has been made and Landlord has fully and
adequately disclosed the existence of any defects which would interfere with
Tenant's use of the Demised Premises for their intended commercial purpose, and
(b) as a result of such inspection and disclosure, Tenant has taken possession
of the Demised Premises and accepts the Demised Premises in its "As Is"
condition.

7.03. MAINTENANCE AND REPAIR. Except as otherwise provided in this Lease,
Landlord shall be under no obligation to perform any repair, maintenance or
management service in the Demised Premises or adjacent common areas. Tenant
shall be fully responsible, at its expense, for all repair, maintenance and
management services other than those which are expressly assumed by Landlord.

      A.    LANDLORD'S OBLIGATION.

            (1)   Subject to the provisions of Article Eight (Damage or
Destruction) and Article Nine (Condemnation) and except for damage caused by any
act or omission of Tenant, Landlord shall keep the roof, skylights, foundation,
structural components and the structural portions of exterior walls of the
Demised Promises in good order, condition and repair. Landlord shall not be
obligated to maintain or repair windows, doors, overhead doors, plate glass or
the surfaces of walls. In addition, Landlord shall not be obligated to make any
repairs under this Section until a reasonable time after receipt of written
notice from Tenant of the need for repairs. If any repairs are required to be
made by Landlord, Tenant shall, at Tenant's sole cost and expense, promptly
remove Tenant's furnishings, fixtures, inventory, equipment and other property,
to the extent required to enable Landlord to make repairs. Landlord's liability
under this Section shall be limited to the cost of those repairs or corrections.
Tenant waives the benefit of any present or future law which might give Tenant
the right to repair the Demised Premises at Landlord's expense or to terminate
the Lease because of the condition.

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            (2)   All repair, maintenance, management and other services to be
performed by Landlord or Landlord's agents involve the exercise of professional
judgment by service providers, and Tenant expressly waives any claims for breach
of warranty arising from the performance of those services, except as due to the
negligence or willful misconduct of any such party(ies).

      B.    TENANT'S OBLIGATION.

            (1)   Subject to the provisions of Section 7.01, Section 7.03.A,
Article Eight (Damage or Destruction) and Article Nine (Condemnation), Tenant
shall, at all times, keep all other portions of the Demised Premises in good
order, condition and repair, ordinary wear and tear excepted, including but not
limited to maintenance, repairs and all necessary replacements of the windows,
plate glass, doors, overhead doors, heating system, ventilating equipment, air
conditioning equipment, electrical and lighting systems, fire protection
sprinkler system, dock levelers, elevators, interior and exterior plumbing, the
interior of the Demised Premises in general, pest control and extermination,
down spouts, gutters, paving, railroad siding, care of landscaping and regular
mowing of grass, and including the exterior of the Demised Premises. In
addition, Tenant shall, at Tenant's expense, repair any damage to any portion of
the Property, including the roof, skylights, foundation, or structural
components and exterior walls of the Demised Premises, caused by Tenant's
negligence or willful misconduct. If Tenant fails to maintain and repair the
Property as required by this Section, Landlord may, on ten (10) days' prior
written notice, enter the Demised Premises and perform the maintenance or repair
on behalf of Tenant, except that no notice is required in case of emergency, and
Tenant shall reimburse Landlord immediately upon demand for all actual and
reasonable costs incurred in performing the maintenance or repair, plus a
reasonable service charge.

            (2)   HVAC SERVICE. Tenant shall, at Tenant's own cost and expense,
perform a regularly scheduled preventative maintenance and service contract for
all refrigeration, heating, ventilating, and air conditioning systems and
equipment within the Demised Premises during the Lease Term. If Tenant fails to
enter into such a service contract acceptable to Landlord, Landlord may do so on
Tenant's behalf and Tenant agrees to pay Landlord the cost and expense thereof,
plus a reasonable service charge, regularly upon demand.

7.04. ALTERATIONS, ADDITIONS AND IMPROVEMENTS. Tenant shall not create any
openings in the roof or exterior walls, or make any alterations, additions or
improvements to the Demised Premises without the prior written consent of
Landlord. Consent for non-structural alterations, additions or improvements
shall not be unreasonably withheld by Landlord. Tenant may erect or install
trade fixtures, shelves, bins, machinery, heating, ventilating and air
conditioning equipment and, provided that Tenant complies with all applicable
governmental laws, ordinances, codes, and regulations. At the expiration or
termination of this Lease, Tenant shall, subject to the restrictions of Section
7.05 below, have the right to remove items installed by Tenant, provided Tenant
is not in default at the time of the removal and provided further that Tenant
shall, at the time of removal of the items, repair in a good and workmanlike
manner any damage caused by the installation or removal. Tenant shall pay for
all costs incurred or arising out of alterations, additions or improvements in
or to the Demised Premises and shall not permit any mechanic's or materialman's
lien to be filed against the Demised Premises or the Property. Upon request by
Landlord, Tenant shall deliver to Landlord proof of payment reasonably
satisfactory to Landlord of all costs incurred or arising out of any
alterations, additions or improvements.

7.05. CONDITION UPON TERMINATION. Upon the expiration or termination of this
Lease, Tenant shall surrender the Demised Premises to Landlord broom clean and
in the same condition as received, except for ordinary wear and tear which
Tenant is not otherwise obligated to remedy under any provision of this Lease.
Tenant shall not be obligated to repair any damage which Landlord is required to
repair under Article Seven (Property Condition) or Article Eight (Damage or
Destruction). In addition, Landlord may require Tenant to remove any
alterations, additions or improvements (whether or not made with Landlord's
consent) prior to the expiration or termination of this Lease and to restore the
Demised Premises to its prior condition, all at Tenant's expense. All
alterations, additions and improvements which Landlord has not required Tenant
to remove shall become Landlord's property and shall be surrendered to Landlord
upon the expiration or termination of this Lease. In no event, however, shall
Tenant remove any of the following materials or equipment without Landlord's
prior written consent: (i) electrical wiring or power panels; (ii) lighting or
lighting fixtures; (iii) wall coverings, drapes, blinds or other window
coverings; (iv) carpets or other floor coverings; (v) heating, ventilating, or
air conditioning equipment; (vi) fencing or security gates; or (vii) any other
fixtures, equipment or items which, if removed, would affect the operation or
the appearance of the Property.

ARTICLE EIGHT: DAMAGE OR DESTRUCTION

8.01. NOTICE. If any buildings or other improvements situated on the Property
are damaged or destroyed by fire, flood, windstorm, tornado or other casualty,
Tenant shall promptly give written notice of the damage or destruction to
Landlord.

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8.02. PARTIAL DAMAGE. If the building or other improvements situated on the
Demised Premises are damaged by fire, tornado, or other casualty but not to such
an extent that rebuilding or repairs cannot reasonably be completed within one
hundred twenty (120) days from the date Landlord receives written notification
by Tenant of the occurrence of the damage, this Lease shall not terminate, but
Landlord shall proceed with reasonable diligence to rebuild or repair the
building and other improvements on the Demised Premises (other than leasehold
improvements made by Tenant or any assignee, subtenant or other occupant of the
Demised Premises) to substantially the condition in which they existed prior to
the damage. If the casualty occurs during the final eighteen (18) months of the
Lease Term, Landlord shall not be required to rebuild or repair the damage
unless Tenant exercises Tenant's renewal option (if any) within fifteen (15)
days after the date of receipt by Landlord of the notification of the occurrence
of the damage. If Tenant does not exercise its renewal option, or if there is no
renewal option contained in this Lease, Landlord may, at Landlord's option,
terminate this Lease by promptly delivering a written termination notice to
Tenant, in which event the Rent shall be abated for the unexpired portion of the
Lease Term, effective from the date of receipt by Landlord of the written
notification of the damage. To the extent the Demised Premises cannot be
occupied (in whole or in part) following the casualty, the Rent payable under
this Lease during the period in which the Demised Premises cannot be fully
occupied shall be adjusted equitably.

8.03. SUBSTANTIAL OR TOTAL DESTRUCTION. If the building or other improvements
situated on the Demised Premises are substantially or totally destroyed by fire,
tornado, or other casualty, or so damaged that rebuilding or repairs cannot
reasonably be completed within one hundred twenty (120) days from the date
Landlord receives written notification by Tenant of the occurrence of the
damage, either Landlord or Tenant may terminate this Lease by promptly
delivering a written termination notice to the other party, in which event the
monthly installments of Rent shall be abated for the unexpired portion of the
Lease Term, effective from the date of the damage or destruction. If neither
party promptly terminates this Lease, Landlord shall proceed with reasonable
diligence to rebuild and repair the building and other improvements (except that
Tenant shall rebuild and repair Tenants fixtures and improvements in the Demised
Premises). To the extent the Demised Premises cannot be occupied (in whole or in
part) following the casualty, the Rent payable under this Lease during the
period in which the Demised Premises cannot be fully occupied shall be adjusted
equitably.

ARTICLE NINE: CONDEMNATION

If, during the Lease Term or any extension thereof, all or a substantial part of
the Demised Premises are taken for any public or quasi-public use under any
governmental law, ordinance or regulation or by right of eminent domain, or are
conveyed to the condemning authority under threat of condemnation, this Lease
shall terminate and the monthly installments of Rent shall be abated during the
unexpired portion of the Lease Term, effective from the date of the taking. If
less than a substantial part of the Demised Premises is taken for public or
quasi-public use under any governmental law, ordinance or regulation, or by
right of eminent domain, or is conveyed to the condemning authority under threat
of condemnation, Landlord, at its option, may by written notice terminate this
Lease. If Landlord does not terminate this Lease, Landlord shall promptly, at
Landlord's expense, restore and reconstruct the buildings and improvements
(other than leasehold improvements made by Tenant or any assignee, subtenant or
other occupant of the Demised Premises) situated on the Demised Premises in
order to make the same reasonably tenantable and suitable for the use for which
the Demised premises is leased as defined in Section 6.01. The monthly
installments of Rent payable under this Lease during the unexpired portion of
the Lease Term shall be adjusted equitably. Landlord and Tenant shall each be
entitled to receive and retain such separate awards and portions of lump sum
awards as may be allocated to their respective interests in any condemnation
proceeding. The termination of this Lease shall not affect the rights of the
parties to such awards.

ARTICLE TEN: ASSIGNMENT AND SUBLETTING SEE ADDENDUM H, SECTION D

Tenant shall not, without the prior written consent of Landlord (which consent
shall not be unreasonably withheld), assign this Lease or sublet the Demised
Premises or any portion thereof. Any assignment or subletting shall be expressly
subject to all terms and provisions of this Lease, including the provisions of
Section 6.01 pertaining to the use of the Demised Promises. In the event of any
assignment or subletting, Tenant shall remain fully liable for the full
performance of all Tenant's obligations under this Lease. Tenant shall not
assign its rights under this Lease or sublet the Demised Premises without first
obtaining a written agreement from the assignee or sublessee whereby the
assignee or sublessee agrees to assume the obligations of Tenant under this
Lease and to be bound by the terms of this Lease. If an event of default occurs
while the Demised Premises is assigned or sublet, Landlord may, at Landlord's
option, in addition to any other remedies provided in this Lease or by law,
collect directly from the assignee or subtenant all rents becoming due under the
terms of the assignment or subletting and apply the rent against any sums due to
Landlord under this Lease. No direct collection by Landlord from any assignee or
subtenent will release Tenant from Tenant s obligations under this Lease.

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ARTICLE ELEVEN: DEFAULT AND REMEDIES

11.01. DEFAULT. Each of the following events is an event of default under this
Lease:

      A.    Failure of Tenant to pay any installment of the Rent or other sum
payable to Landlord under this Lease on the date that it is due and the
continuance of that failure for a period of five (5) days after Landlord
delivers written notice of the failure to Tenant. This clause shall not be
construed to permit or allow a delay as paying Rent beyond the due date and
shall not affect Landlord's right to impose a Late Charge as permitted in
Section 3.03.

      B.    Failure of Tenant to comply with any term, condition or covenant of
this Lease, other than the payment of Rent or other sum of money, and the
continuance of that failure for a period of thirty (30) days after Landlord
delivers written notice of the failure to Tenant;

      C.    Failure of Tenant or any guarantor of Tenant's obligations under
this Lease to pay its debts as they become due or an admission in writing of
inability to pay its debts, or the making of a general assignment for the
benefit of creditors;

      D.    The commencement by Tenant or any guarantor of Tenant's obligations
under this Lease of any case, proceeding or other action seeking reorganization,
arrangement, adjustment, liquidation, dissolution or composition of it or its
debts under any law relating to bankruptcy, insolvency, reorganization or relief
of debtors, or seeking appointment of a receiver, trustee, custodian or other
similar official for it or for all or any substantial part of its property;

      E.    The commencement of any case, proceeding or other action against
Tenant or any guarantor of Tenant's obligations under this Lease seeking to have
an order for relief entered against it as debtor, or seeking reorganization,
arrangement, adjustment, liquidation, dissolution or composition of it or its
debts under any law relating to bankruptcy, insolvency, reorganization or relief
of debtors, or seeking appointment of a receiver, trustee, custodian or other
similar official for it or for all or any substantial part of its property, and
Tenant or any guarantor: (i) fails to obtain a dismissal of such case,
proceeding, or other action within sixty (60) days of its commencement; or (ii)
converts the case from one chapter of the Federal Bankruptcy Code to another
chapter; or (iii) is the subject of an order of relief which is not fully stayed
within seven (7) business days after the entry thereof; and

      F.    Vacancy or abandonment by Tenant of any substantial portion of the
Demised Premises or cessation of the use of the Demised Premises for the purpose
leased.

11.02. REMEDIES. Upon the occurrence of any of the events of default listed in
Section 11.01, Landlord shall have the option to pursue any one or more of the
following remedies without any prior notice or demand.

      A.    Terminate this Lease, in which event Tenant shall immediately
surrender the Demised Premises to Landlord. If Tenant fails to so surrender the
Demised Premises, Landlord may, without prejudice to any other remedy which it
may have for possession of the Demised Premises or Rent in arrears, enter upon
and take possession of the Demised Premises and expel or remove Tenant and any
other person who may be occupying the Demised Premises or any part thereof, by
force if necessary, without being liable for prosecution or any claim for
damages. Tenant shall pay to Landlord on demand the amount of all loss and
damage which Landlord may suffer by reason of the termination, whether through
inability to re-let the Demised Premises on satisfactory terms or otherwise.

      B.    Enter upon and take possession of the Demised Premises, by force if
necessary, without terminating this Lease and without being liable for
prosecution or for any claim for damages, and expel or remove Tenant and any
other person who may be occupying the Demised Premises or any part thereof.
Landlord may re-let the Demised Premises and receive the rent therefor. Tenant
agrees to pay to Landlord monthly or on demand from time to time any deficiency
that may arise by reason of any such re-letting. In determining the amount of
the deficiency, the professional service fees, attorneys' fees, court costs,
remodeling expenses and other costs of re-letting shall be subtracted from the
amount of rent received under the re-letting.

      C.    Enter upon the Demised Premises, by force if necessary, without
terminating this Lease and without being liable for prosecution or for any claim
for damages, and do whatever Tenant is obligated to do under the terms of this
Lease. Tenant agrees to pay Landlord on demand for expenses which Landlord may
incur in thus effecting compliance with Tenant's obligations under this Lease,
together with interest thereon at the rate of twelve percent (12%) per annum
from the

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date expended until paid. Landlord shall not be liable for any damages resulting
to Tenant from such action, whether caused by negligence of Landlord or
otherwise.

      D.    Accelerate and declare the Rent for the entire Lease Term, and all
other amounts due under this Lease, at once due and payable, and proceed by
attachment, suit or otherwise, to collect all amounts in the same manner as if
all such amounts due or to become due during the entire Lease Term were payable
in advance by the terms of this Lease, and neither the enforcement or collection
by Landlord of such amounts nor the payment by Tenant of such amounts shall
constitute a waiver by Landlord of any breach, existing or in the future, of any
of the terms or provisions of this Lease by Tenant or a waiver of any rights or
remedies which the Landlord may have with respect to any such breach.

      E.    In addition to the foregoing remedies, Landlord shall have the right
to change or modify the locks on the Demised Premises in the event Tenant fails
to pay the monthly installment of Rent when due. Landlord shall not be obligated
to provide another key to Tenant or allow Tenant to regain entry to the Demises
Premises unless and until Tenant pays Landlord all Rent which is delinquent.
Tenant agrees that Landlord shall not be liable for any damages resulting to the
Tenant from the lockout. At such time that Landlord changes or modifies the
lock, Landlord shall post a "Notice of Change of Locks" on the front of the
Demised Premises. Such Notice shall state that:

            (1)   Tenant's monthly installment of Rent is delinquent, and
therefore, under authority of Section 11.02.E of Tenant's Lease, the Landlord
has exercised its contractual right to change or modify Tenant's door locks;

            (2)   The Notice has been posted on the Tenant's front door by a
representative of Landlord and Tenant should make arrangements with the
representative to pay the delinquent installments of Rent when Tenant picks up
the key; and

            (3)   The failure of Tenant to comply with the provisions of the
Lease and the Notice and/or tampering with or changing the door lock(s) by
Tenant may subject Tenant to legal liability.

      F.    No re-entry or taking possession of the Demised Premises by Landlord
shall be construed as an election to terminate this Lease, unless a written
notice of that intention is given to Tenant. Pursuit of any of the foregoing
remedies shall not preclude pursuit of any other remedies provided by law, nor
shall pursuit of any remedy provided in this Lease constitute a forfeiture or
waiver of any monthly installment of Rent due to Landlord under this Lease or of
any damages accruing to Landlord by reason of the violation of any of the terms,
provisions and covenants contained in this Lease. Failure of Landlord to declare
any default immediately upon its occurrence, or failure to enforce one or more
of Landlord's remedies, or forbearance by Landlord to enforce one or more of
Landlord's remedies upon an event of default shall not be deemed or construed to
constitute a waiver of default or waiver of any violation or breach of the terms
of this Lease. Pursuit of any one of the above remedies shall not preclude
pursuit by Landlord of any of the other remedies provided in this Lease. The
loss or damage that Landlord may suffer by reason of termination of this Lease
or the deficiency from any re-letting as provided for above shall include the
expense of repossession and any repairs or remodeling undertaken by Landlord
following possession. If Landlord terminates this Lease at any time for any
default, in addition to other Landlord's remedies, Landlord may recover from
Tenant all damages Landlord may incur by reason of the default, including the
cost of recovering the Demised Premises and the Rent then remaining unpaid.

11.03. NOTICE OF DEFAULT. Tenant shall give written notice of any failure by
Landlord to perform any of Landlord's obligations under this Lease to Landlord
and to any ground lessor, mortgagee or beneficiary under any deed of trust
encumbering the Demised Premises whose name and address have been furnished to
Tenant in writing. Landlord shall not be in default under this Lease unless
Landlord (or such ground lessor, mortgagee or beneficiary) fails to cure the
nonperformance within thirty (30) days after receipt of Tenant's notice.
However, if the nonperformance reasonably requires more than thirty (30) days to
cure, Landlord shall not be in default if the cure is commenced within the
30-day period and is thereafter diligently pursued to completion.

11.04. LIMITATION OF LANDLORD'S LIABILITY. As used in this Lease, the term
"Landlord" means only the current owner or owners of the fee title to the
Demised Premises or the leasehold estate under a ground lease of the Demised
Premises at the time in question. Each Landlord is obligated to perform the
obligations of Landlord under this Lease only during the time such Landlord owns
such interest or title. Any Landlord who transfers its title or interest is
relieved of all liability with respect to the obligations of Landlord under this
Lease accruing on or after the date of transfer, and Tenant agrees to recognize
the transferee as Landlord under this Lease. However, each Landlord shall
deliver to its transferee the Security Deposit held by Landlord if such Security
Deposit has not then been applied under the terms of this Lease.

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ARTICLE TWELVE: LANDLORD'S CONTRACTUAL LIEN

In addition to the statutory Landlord's lien, Tenant hereby grants to Landlord a
security interest to secure payment of all Rent and other sums of money becoming
due under this Lease from Tenant, upon all inventory, goods, wares, equipment,
fixtures, furniture and all other personal property of Tenant situated in or
upon the Demised Premises, together with the proceeds from the sale or lease
thereof. Tenant may not remove such property without the consent of Landlord
until all Rent in arrears and other sums of money then due to Landlord under
this Lease have first been paid and discharged. Upon the occurrence of an event
of default, Landlord may, in addition to any other remedies provided in this
Lease or by law, enter upon the Demised Premises and take possession of any and
all goods, wares, equipment, fixtures, furniture and other personal property of
Tenant situated on the Demised Premises without liability for trespass or
conversion, and sell the property at public or private sale, with or without
having the property at the sale, after giving Tenant reasonable notice of the
time and place of any such sale. Unless otherwise required by law, notice to
Tenant of the sale shall be deemed sufficient if given in the manner prescribed
in this Lease at least ten (10) days before the time of the sale. Any public
sale made under this Article shall be deemed to have been conducted in a
commercially reasonable manner if held on the Demised Premises or where the
property is located, after the time, place and method of sale and a general
description of the types of property to be sold have been advertised in a daily
newspaper published in the county where the Demised Premises is located for five
(5) consecutive days before the date of the sale. Landlord or its assigns may
purchase at a public sale and, unless prohibited by law, at a private sale. The
proceeds from any disposition dealt with in this Article, less any and all
expenses connected with the taking of possession, holding and selling of the
property (including reasonable attorneys' fees and legal expenses), shall be
applied as a credit against the indebtedness secured by the security interest
granted herein. Any surplus shall be paid to Tenant or as otherwise required by
law, and Tenant shall promptly pay any deficiencies. Upon request by Landlord,
Tenant agrees to execute and deliver to Landlord a Financing Statement in a form
sufficient to perfect the security interest of Landlord in the aforementioned
property and proceeds thereof under the provisions of the Business and Commerce
Code in force in the State of Texas. The statutory lien for rent is expressly
reserved; the security interest herein granted is in addition and supplementary
thereto. Provided Tenant is not in default under any of the terms of this Lease,
upon written request by Tenant Landlord shall deliver a written subordination of
Landlord's statutory and contractual liens to any liens and security interests
securing any institutional third party financing of Tenant. Landlord shall not
unreasonably withhold or delay the delivery of Landlord's written subordination.

ARTICLE THIRTEEN: PROTECTION OF LENDERS

13.01. SUBORDINATION AND ATTORNMENT. Landlord shall have the right to
subordinate this Lease to any future ground Lease, deed of trust or mortgage
encumbering the Demised Premises, and advances made on the security thereof and
any renewals, modifications. consolidations, replacements or extensions thereof,
whenever made or recorded. Landlord's right to obtain such a subordination is
subject to Landlord's providing Tenant with a written Subordination,
Non-disturbance and Attornment Agreement from the ground lessor, beneficiary or
mortgagee wherein Tenant's right to peaceable possession of the Demised Premises
during the Lease Term shall not be disturbed if Tenant pays the Rent and
performs all of Tenant's obligations under this Lease and is not otherwise in
default, in which case Tenant shall attorn to the transferee of or successor to
Landlord's interest in the Demised Premises and recognize the transferee or
successor as Landlord under this Lease. If any ground lessor, beneficiary or
mortgagee elects to have this Lease superior to the lien of its ground lease,
deed of trust or mortgage and gives Tenant written notice thereof, this Lease
shall be deemed superior to the ground lease, deed of trust or mortgage whether
this Lease is dated prior or subsequent to the date of the ground lease, deed of
trust or mortgage or the date of recording thereof. Tenant's rights under this
Lease, unless specifically modified at the time this Lease is executed, are
subordinated to any existing ground lease, deed of trust or mortgage encumbering
the Demised Premises.

13.02. Tenant shall sign and deliver any instruments or documents necessary or
appropriate to evidence any attornment or subordination or any agreement to
attorn or subordinate.

13.03. ESTOPPEL CERTIFICATES.

      A.    Upon Landlord's written request, Tenant shall execute and deliver to
Landlord a written statement certifying: (1) whether Tenant is an assignee or
subtenant; (2) the expiration date of the Lease; (3) the number of renewal
options under the lease and the total period of time covered by the renewal
option(s); (4) that none of the terms or provisions of the Lease have been
changed since the original execution of the Lease, except as shown on attached
amendments or modifications; (5) that no default by Landlord exists under the
terms of the Lease (or if Landlord is claimed to be in default, stating why);
(6) that the Tenant has no claim against the landlord under the Lease and has no
defense or right of offset against collection of rent or other charges accruing
under the Lease; (7) the amount and date of the last

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payment of Rent; (8) the amount of any security deposits and other deposits, if
any; and (9) the identity and address of any guarantor of the lease. Tenant
shall deliver the statement to Landlord within ten (10) business days after
Landlord's request. Landlord may forward any such statement to any prospective
purchaser or lender of the Demised Premises. The purchaser or lender may rely
conclusively upon the statement as true and correct.

      B.    If Tenant does not deliver the written statement to Landlord within
the ten (10) business day period, Landlord, and any prospective purchaser or
lender, may conclusively presume and rely upon the following facts: (1) that the
terms and provisions of this Lease have not been changed except as otherwise
represented by Landlord; (2) that this Lease has not been canceled or terminated
except as otherwise represented by Landlord; (3) that not more than one monthly
installment of Base Rent and other charges have been paid in advance; (4) there
are no claims against Landlord nor any defenses or rights of offset against
collection of Rent or other charges; and (5) that Landlord is not in default
under this Lease. In such event, Tenant shall be estopped from denying the truth
of the presumed facts.

13.04. TENANT'S FINANCIAL CONDITION. Within ten (10) days after written request
from Landlord, Tenant shall deliver to Landlord financial statements as are
reasonably required by Landlord to verify the net worth of Tenant, or any
assignee, subtenant, or guarantor of Tenant. In addition, Tenant shall deliver
to any lender designated by Landlord any financial statements required by the
lender to facilitate the financing or refinancing of the Demised Promises.
Tenant represents and warrants to Landlord that each financial statement is a
true, complete, and accurate statement as of the date of the statement. All
financial statements shall be confidential and shall be used only for the
purposes set forth in this Lease.

ARTICLE FOURTEEN: ENVIRONMENTAL REPRESENTATIONS AND INDEMNITY

14.01. TENANT'S COMPLIANCE WITH ENVIRONMENTAL LAWS. Tenant, at Tenant's expense,
shall comply with all laws, rules, orders, ordinances, directions, regulations
and requirements of Federal, State, county and municipal authorities pertaining
to Tenant's use of the Property and with the recorded covenants, conditions and
restrictions, regardless of when they become effective, including, without
limitation, all applicable Federal, State and local laws, regulations or
ordinances pertaining to air and water quality, Hazardous Materials (as defined
in Section 14.05), waste disposal, air emissions and other environmental
matters, all zoning and other land use matters, and with any direction of any
public officer or officers, pursuant to law, which impose any duty upon Landlord
or Tenant with respect to the use or occupancy of the Property.

14.02. TENANT'S INDEMNIFICATION. SEE ADDENDUM H, SECTION B. Tenant shall not
cause or permit any Hazardous Materials to be brought upon, kept or used in or
about the Property by Tenant, its agents, employees, contractors or invitees
without the prior written consent of Landlord subject to ADDENDUM H, SECTION B
attached hereto. If Tenant breaches the obligations stated in the preceding
Section or sentence, or if the presence of Hazardous Materials on the Property
caused or permitted by Tenant results in contamination of the Property or any
other property, or if contamination of the Property or any other property by
Hazardous Materials otherwise occurs for which Tenant is legally liable to
Landlord for damage resulting therefrom, then Tenant shall indemnify, defend and
hold Landlord harmless from any and all claims, judgments, damages, penalties,
fines, costs, liabilities or losses (including, without limitation, diminution
in value of the Property, damages for the loss or restriction on use of rentable
or unusable space or of any amenity or appurtenance of the Property, damages
arising from any adverse impact on marketing of building space or land area,
sums paid in settlement of claims, reasonable attorneys' fees, court costs,
consultant fees and expert fees) which arise during or after the Lease Term as a
result of the contamination. This indemnification of Landlord by Tenant
includes, without limitation, costs incurred in connection with any
investigation of site conditions or any clean-up, remedial work, removal or
restoration work required by any Federal, State or local government agency
because of Hazardous Materials present in the soil or ground water on or under
the Property. Without limiting the foregoing, if the presence of any Hazardous
Materials on the Property (or any other property) caused or permitted by Tenant
results in any contamination of the Property, Tenant shall promptly take all
actions at Tenant's sole expense as are necessary to return the Property to the
condition existing prior to the introduction of any such Hazardous Materials,
provided that Landlord's approval of such actions is first obtained. The
foregoing indemnity shall survive the expiration or termination of this Lease.

14.03. LANDLORD'S REPRESENTATIONS AND WARRANTIES. Landlord represents and
warrants, to the best of Landlord's actual knowledge, that: (i) any handling,
transportation, storage, treatment or usage of Hazardous Materials that has
occurred on the Property to date has been in compliance with all applicable
Federal, State, and local laws, regulations and ordinances; and (ii) no leak,
spill, release, discharge, emission or disposal of Hazardous Materials has
occurred on the Property to date and that the soil or groundwater on or under
the Property is free of Hazardous Materials as of the Commencement Date, unless
expressly disclosed by Landlord to Tenant in writing.

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14.04. LANDLORD'S INDEMNIFICATION. Landlord hereby indemnifies, demands and
holds Tenant harmless from any claims, judgments, damages, penalties, fines,
costs, liabilities, (including sums paid in settlements of claims) or loss,
including, without limitation, attorneys' fees, court costs, consultant fees,
and expert fees, Which arise during or after the term of this Lease from or in
connection with the presence or suspected presence of Hazardous Materials in the
soil of groundwater on or under the Property, unless the Hazardous Material is
released by Tenant or is present solely as a result of the negligence or willful
conduct of Tenant. Without limiting the generality of the foregoing, the
indemnification provided by this Section 14.04 shall specifically cover costs
incurred in connection with any investigation of site conditions or any
clean-up, remedial work, removal or restoration work required by any Federal,
State or local governmental authority.

14.05. DEFINITION. For purposes of this Lease, the term "Hazardous Materials"
means any one or more pollutant, toxic substance, hazardous waste, hazardous
material, hazardous substance, solvent or oil as defined in or pursuant to the
Resource Conservation and Recovery Act, as amended, the Comprehensive
Environmental Response, Compensation and Liability Act, as amended, the Federal
Clean Water Act, as amended, or any other Federal, State or local environmental
law, regulation, ordinance, or rule, whether existing as of the date of this
Lease or subsequently enacted.

14.06. SURVIVAL. The representations and indemnities contained in this Article
14 shall survive the expiration or termination of this Lease.

ARTICLE FIFTEEN: PROFESSIONAL SERVICE FEES

15.01. AMOUNT AND MANNER OF PAYMENT. Professional service fees due to the
Principal Broker shall be calculated and paid as follows:

      A.    Landlord agrees to pay to the Principal Broker a monthly
professional service fee (the "Fee") for negotiating this Lease, plus any
applicable sales taxes, equal to the percentage stated in Section 1.13.A of each
monthly Rent payment at the time the payment is due.

      B.    Landlord agrees to pay to the Principal Broker a lump sum
professional service fee (the "Fee") for negotiating this Lease, plus any
applicable sales taxes, equal to the percentage stated in Section 1.13.A of the
total Rent to become due to Landlord during the Lease Term.

15.02. OTHER BROKERS. Both Landlord and Tenant represent and warrant to the
other party that they have had no dealings with any person, firm or agent in the
negotiation of this Lease other than the Broker(s) named in this Lease, and no
other broker, agent, person, firm or entity other than the Broker(s) is entitled
to any commission or fee in connection with this Lease.

15.03. PAYMENTS ON RENEWAL, EXPANSION, EXTENSION OR NEW LEASE. If during the
Lease Term (as may be renewed or extended) or within ten (10) years from the
Commencement Date, whichever is the greater period of time, Tenant, Tenant's
successors or assigns: (a) exercises any right or option to renew or extend the
Lease Term (whether contained in this Lease or in any amendment, supplement or
other agreement pertaining to this Lease) or enters into a new lease or rental
agreement with Landlord covering the Demised Premises; or (b) enters into any
lease, extension, renewal, expansion or ether rental agreement with Landlord
demising to Tenant any premises located on or constituting all or part of any
tract or parcel of real property adjoining, adjacent to or contiguous to the
Demised Premises and owned by Landlord on the Commencement Date, Landlord shall
pay to the Principal Broker an additional Fee covering the full period of the
renewal, extension, lease, expansion or other rental agreement which shall be
due on the date of exercise of a renewal option, or the date of execution in the
case of an extension, new lease, expansion or other agreement. The additional
Fee shall be computed under Section 15.0l.A or 15.01.B above (whichever has been
made applicable under Section 1.13), as if a new lease had been made for such
period of time.

15.04. PAYMENTS ON SALE. If Tenant, Tenant's successors or assigns, purchases
the Demised Premises at any time, pursuant to a purchase option contained in
this Lease (or any lease, extension, renewal, expansion or other rental
agreement) or, in the absence of any purchase option or exercise thereof,
purchases the Demised Premises within ten (10) years from the Commencement Date,
Landlord shall pay to the Principal Broker a Professional Service Fee in cash
equal to the percentage stated in Section 1.13.B of the purchase price, payable
at closing. Upon closing of a sale to Tenant, all monthly lease Fees shall
terminate upon payment of the Professional Service Fee on the sale.

15.05. LANDLORD'S LIABILITY. If this Lease is negotiated by Principal Broker in
cooperation with another broker, Landlord shall be liable for payment of all
Professional Service Fees to Principal Broker only, whereupon Landlord shall be
protected

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<PAGE>
from any claims from a Cooperating Broker. The Principal Broker may pay a
portion of the Fee to any Cooperating Broker pursuant to a separate agreement
between the Brokers.

15.06. JOINT LIABILITY OF TENANT. If Tenant enters into any new lease,
extension, renewal, expansion, or other agreement to rent, occupy, or purchase
any property described in Section 15.03 within the time specified in that
Section, the agreement must be handled by the Principal Broker, otherwise Tenant
shall be jointly and severally liable with Landlord for any payments due or to
become due to the Principal Broker.

15.07. ASSUMPTION ON SALE. In the event of a sale of the Demised Premises or the
assignment of this Lease by Landlord, Landlord shall obtain from the purchaser
or assignee an Assumption Agreement in recordable form whereby the purchaser or
assignee agrees to pay the Principal Broker all Professional Service Fees
payable under this Lease and shall deliver a fully executed original counterpart
thereof to Principal Broker on the date of closing of the sale of the Demised
Premises or assignment of this Lease. Landlord shall be released from personal
liability for subsequent payments only upon the delivery to Principal Broker of
that counterpart of the Assumption Agreement.

15.08. TERMINATION. The termination of this Lease by the mutual agreement of
Landlord and Tenant shall not affect the right of the Principal Broker to
continue to receive the Fees agreed to be paid under this Lease, just as if
Tenant had continued to occupy the Demised Premises and had paid the Rent during
the entire Lease Term. Termination of this Lease under Article Eight or Article
Nine shall not terminate the Principal Broker's right to collect the Fees.

15.09. INTERMEDIARY RELATIONSHIP.

      A.    If either Principal Broker and/or Cooperating Broker (together, the
"Brokers") has indicated in Sections 1.11 and 1.12 that they are acting as an
intermediary, then Landlord and Tenant hereby authorize the applicable Broker(s)
to act as an intermediary between Landlord and Tenant in connection with this
Lease, and acknowledge that the source of any expected compensation to the
Brokers will be Landlord, and the Brokers may also be paid a fee by the Tenant.
A REAL ESTATE BROKER WHO ACTS AS AN INTERMEDIARY BETWEEN PARTIES IN A
TRANSACTION:

            (1)   MAY NOT DISCLOSE TO TENANT THAT LANDLORD WILL ACCEPT A RENT
LESS THAN THE ASKING RENT UNLESS OTHERWISE INSTRUCTED IN A SEPARATE WRITING BY
LANDLORD;

            (2)   MAY NOT DISCLOSE TO LANDLORD THAT TENANT WILL PAY A RENT
GREATER THAN THE RENTAL SUBMITTED IN A WRITTEN OFFER TO LANDLORD UNLESS
OTHERWISE INSTRUCTED IN A SEPARATE WRITING BY TENANT;

            (3)   MAY NOT DISCLOSE ANY CONFIDENTIAL INFORMATION, OR ANY
INFORMATION A PARTY SPECIFICALLY INSTRUCTS THE REAL ESTATE BROKER IN WRITING NOT
TO DISCLOSE, UNLESS OTHERWISE INSTRUCTED IN A SEPARATE WRITING BY THE RESPECTIVE
PARTY OR REQUIRED TO DISCLOSE SUCH INFORMATION BY THE TEXAS REAL ESTATE LICENSE
ACT OR A COURT ORDER OR IF THE INFORMATION MATERIALLY RELATES TO THE CONDITION
OF THE PROPERTY;

            (4)   SHALL TREAT ALL PARTIES TO THE TRANSACTION HONESTLY; AND

            (5)   SHALL COMPLY WITH THE TEXAS REAL ESTATE LICENSE ACT.

      B.    APPOINTMENTS. Broker is authorized to appoint, by providing written
notice to the parties, one or more licensees associated with Broker to
communicate with and carry out instructions of one party, and one or more other
licensees associated with Broker to communicate with and carry out instructions
of the other party or parties. During negotiations, an appointed licensee may
provide opinions and advice to the party to whom the licensee is appointed.

ARTICLE SIXTEEN: MISCELLANEOUS

16.01. DISCLOSURE. Landlord and Tenant understand that a real estate broker is
qualified to advise on matters concerning real estate and is not expert in
matters of law, tax, financing, surveying, hazardous materials, engineering,
construction, safety, zoning, land planning, architecture or the ADA. The
Brokers hereby advise Tenant to seek expert assistance on such matters. Brokers
do not investigate a property's compliance with building codes, governmental
ordinances, statutes and laws that relate to the use or condition of a property
and its construction, or that relate to its acquisition. If Brokers provide
names of consultants or sources for advice or assistance, Tenant acknowledges
that the Brokers do not warrant the services of the advisors or their products
and cannot warrant the suitability of property to be acquired or leased.
Furthermore, the Brokers do not warrant that the Landlord will disclose any or
all property defects, although the Brokers will disclose to Tenant any actual
knowledge possessed by Brokers regarding defects of the Demised Premises and the
Property. In this regard, Tenant agrees to make all necessary and appropriate
inquiries and to use diligence in investigating the Demised Premises and the
Property before consummating this Lease. Landlord and Tenant hereby agree to
indemnify, defend, and hold the Brokers harmless of and from any and all
liabilities, claims, debts, damages, costs, or expenses, including but not
limited to reasonable attorneys' fees and court costs, related to or arising out
of or in any way connected to representations

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<PAGE>
concerning matters properly the subject of advice by experts. In addition, to
the extent permitted by applicable law, the Brokers' liability for errors or
omissions, negligence, or otherwise, is limited to the return of the Fee, if
any, paid to the Brokers pursuant to this Lease.

16.02. FORCE MAJEURE. If performance by Landlord or Tenant of any term,
condition or covenant in this Lease is delayed or prevented by any Act of God,
strike, lockout, shortage of material or labor, restriction by any governmental
authority, civil riot, flood, or any other cause not within the control of such
party, the period for performance of the term, condition or covenant shall be
extended for a period equal to the period such party is so delayed or prevented.

16.03. INTERPRETATION. The captions of the Articles or Sections of this Lease
are to assist the parties in reading this Lease and are not a part of the terms
or provisions of this Lease. Tenant shall be responsible for the conduct, acts
and omissions of Tenant's agents, employees, customers, contractors, invitees,
agents, successors or others using the Demised Premises with Tenant's expressed
or implied permission. Whenever required by the context of this Lease, the
singular shall include the plural and the plural shall include the singular, and
the masculine, feminine and neuter genders shall each include the other.

16.04. WAIVERS. All waivers to provisions of this Lease must be in writing and
signed by the waiving party. Landlord's delay or failure to enforce any
provisions of this Lease or its acceptance of late installments of Rent shall
not be a waiver and shall not prevent Landlord from enforcing that provision or
any other provision of this Lease in the future. No statement on a payment check
from Tenant or in a letter accompanying a payment check shall be binding on
Landlord. Landlord may, with or without notice to Tenant, negotiate, cash, or
endorse the check without being bound to the conditions of any such statement.

16.05. SEVERABILITY. A determination by a court of competent jurisdiction that
any provision of this Lease is invalid or unenforceable shall not cancel or
invalidate the remainder of that provision or this Lease, which shall remain in
full force and effect.

16.06. JOINT AND SEVERAL LIABILITY. All parties signing this Lease as Tenant
shall be jointly and severally liable for all obligations of Tenant.

16.07. AMENDMENTS OR MODIFICATIONS. This Lease is the only agreement between the
parties pertaining to the lease of the Demised Premises and no other agreements
are effective unless made a part of this Lease. All amendments to this Lease
must be in writing and signed by all parties. Any other attempted amendment
shall be void.

16.08. NOTICES. All notices and other communications required or permitted under
this Lease must be in writing and shall be deemed delivered, whether actually
received or not, on the earlier of: (i) actual receipt if delivered in person or
by messenger with evidence of delivery; or (ii) receipt of an electronic
facsimile transmission ("Fax") with confirmation of delivery; or (iii) upon
deposit in the United States Mail as required below. Notices may be transmitted
by Fax to the Fax telephone numbers specified in Article One on the first page
of this Lease, if any. Notices delivered by mail must be deposited in the U.S.
Postal Service, first class postage prepaid, and properly addressed to the
intended recipient as set forth in Article One. After possession of the Demised
Premises by Tenant, Tenant's address for notice purposes will be the address of
the Demised Premises unless Tenant notifies Landlord in writing of a different
address to be used for that purpose. Any party may change its address for notice
by delivering written notice of its new address to all other parties in the
manner set forth above. Copies of all notices should also be delivered to the
Principal Broker, but failure to notify the Principal Broker will not cause an
otherwise properly delivered notice to be ineffective.

16.09. ATTORNEYS' FEES. If on account of any breach or default by any party to
this Lease in its obligations to any other party to this Lease (including but
not limited to the Principal Broker), it becomes necessary for a party to employ
an attorney to enforce or defend any of its rights or remedies under this Lease,
the non-prevailing party agrees to pay the prevailing party its reasonable
attorneys' fees and court costs, if any, whether or not suit is instituted in
connection with the enforcement or defense.

16.10. VENUE. All obligations under this Lease, including but not limited to the
payment of Fees to the Principal Broker, shall be performed and payable in the
county in which the Property is located. The laws of the State of Texas shall
govern this Lease.

16.11. SURVIVAL. All obligations of any party to this Lease which are not
fulfilled at the expiration or the termination of this Lease shall survive such
expiration or termination as continuing obligations of the party.

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<PAGE>
16.12. BINDING EFFECT. This Lease shall inure to the benefit of, and be binding
upon, each of the parties to this Lease and their respective heirs,
representatives, successors and assigns. However, Landlord shall not have any
obligation to Tenant's successors or assigns unless the rights or interests of
the successors or assigns are acquired in accordance with the terms of this
Lease.

16.13. CONSULT AN ATTORNEY. THIS LEASE IS AN ENFORCEABLE, LEGALLY BINDING
AGREEMENT. READ IT CAREFULLY. The brokers involved in the negotiation of this
Lease cannot give you legal advice. The parties to this Lease acknowledge that
they have been advised by the Brokers to have this Lease reviewed by competent
legal counsel of their choice before signing this Lease. By executing this
Lease, Landlord and Tenant each agree to the previsions, terms, covenants and
conditions contained in this Lease.

16.14. OFFER. The execution of this Lease by the first party to do so
constitutes an offer to lease the Demised Premises. Unless within the number of
days stated in Section 1.14 above after the date of its execution by the first
party to do so, this Lease is signed by the other party and a fully executed
copy is delivered to the first party, such offer to lease shall be automatically
withdrawn and terminated.

ARTICLE SEVENTEEN: ADDITIONAL PROVISIONS

A.    LANDLORD AGREES TO ABATE THE RENT FROM JUNE THROUGH NOVEMBER OF 2002 IN
EXCHANGE FOR TENANT'S PAYING FOR IMPROVEMENTS (WHICH SHALL BE APPROVED BY
LANDLORD) AS SHOWN IN PARAGRAPH E OF ADDENDUM H.

B.    15.01 (CONTINUED) COMMISSION SHALL BE PAYABLE ON NONCANCELABLE LEASE UPON
THE ACCEPTANCE AND OCCUPANCY OF THE PREMISES. THE REMAINDER OF THE COMMISSION
SHALL BE DUE WHEN EARLEY TERMINATION OPTION EXPIRES WITHOUT BEING EXERCISED.

C.    LANDLORD AGREES TO PAY FOR THE INSTALLATION OF A FLOW BACK PREVENTION
VALVE AS REQUIRED BY THE TOWN OF ADDISON FOR DOMESTIC WATER.

D.    TENANT AGREES TO PAY THE ADDITIONAL PREMIUM, IF ANY, REQUIRED FOR ITS USE
UNDER SECTION 5.02.

E.    LANDLORD AGREES TO ABATE THE ASBESTOS AS REQUIRED IN THE APRIL 2002 REPORT
BY LONE TREE RESOURCES AND CONSULTING. TENANT AND LANDLORD WILL MUTUALLY AGREE
ON THE SCOPE OF WORK.

<TABLE>
<S>                                                      <C>
LANDLORD                                                 TENANT

TOM TAYLOR, ARCH JACOBSON, AND ESTATE OF JAMES MORAN     PROBEX CORP.
----------------------------------------------------     ----------------------------------------------------

By: [Signature]: /s/ Tom Taylor                          By: [Signature]: /s/ Bruce Hall
                 -----------------------------------                      -----------------------------------
Name:             Tom Taylor                             Name:             Bruce Hall
      ----------------------------------------------           ----------------------------------------------
Title:            Managing Director                      Title:            SVP & CFO
       ---------------------------------------------            ---------------------------------------------
Date of Execution:         5-19-2002                     Date of Execution:        5/14/02
                   ---------------------------------                        ---------------------------------

PRINCIPAL BROKER                                         COOPERATING BROKER
----------------------------------------------------     ----------------------------------------------------

PATRICK J. HAGGERTY (2%)                                 MILLER COMMERCIAL (4%)

By: [Signature]:                                         By: [Signature]:
                 -----------------------------------                      -----------------------------------
Name: Patrick J. Haggerty                                Name: Dan Spika
      ----------------------------------------------           ----------------------------------------------
Title:                                                   Title:
       ---------------------------------------------            ---------------------------------------------
Date of Execution:                                       Date of Execution:
                   ---------------------------------                        ---------------------------------
</TABLE>

Copyright Notice: This form is provided for the use of members of the North
Texas Commercial Association of Realtors, Inc. Permission is hereby granted to
make limited copies of this form for use in a particular Texas real estate
transaction. Contact the NTCAR office to confirm that you are using the current
version of this form.

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<PAGE>
                                    EXHIBIT A

                               [SITE DESCRIPTION]
<PAGE>
                                    EXHIBIT B

                               [SITE DESCRIPTION]
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                                  PAT HAGGERTY

               NORTH TEXAS COMMERCIAL ASSOCIATION OF REALTORS(R)

                              ADDENDUM A TO LEASE

                             EXPENSE REIMBURSEMENT

DEMISED PREMISES/ADDRESS: 15510 Wright Brothers Drive, Addison, Texas 75001

  [CHECK ALL BOXES WHICH APPLY. BOXES NOT CHECKED DO NOT APPLY TO THIS LEASE.]

A.    EXPENSE REIMBURSEMENT. Tenant shall pay the Landlord as additional Rent a
portion of the following expenses (collectively the "Reimbursement") which are
incurred by or assessed against the Demised Premises [CHECK ALL THAT ARE TO
APPLY]:

      [X]    Ad Valorem Taxes;
      [X]    Insurance Premiums;
      [ ]    Common Area Maintenance (CAM) Expenses;
      [ ]    Operating Expenses;
      [ ]    Roof and Structural Maintenance Expenses;

B.    EXPENSE REIMBURSEMENT LIMITATIONS. The amount of Tenant's Reimbursement
shall be determined by one of the following methods as described in Section 4
below [CHECK ONLY ONE]:

      [X]    Base Year/Expense Stop Adjustment;
      [ ]    Pro Rata Adjustment;
      [ ]    Fixed Amount Adjustment;
      [ ]    Net Lease Provisions.

C.    EXPENSE REIMBURSEMENT PAYMENTS. Tenant agrees to pay any end-of-year lump
sum Reimbursement within thirty (30) days after receiving an invoice from
Landlord. Any time during the Lease Term (or any renewals or extensions)
Landlord may direct Tenant to pay monthly an estimated portion of the projected
future Reimbursement amount. Any such payment directed by Landlord shall be due
and payable monthly on the same day that the Base Rent is due. Landlord may, at
Landlord's option and to the extent allowed by applicable law, impose a Late
Charge on any Reimbursement payments which are not actually received by Landlord
on or before the due date, in the amount and manner set forth in Section 3.03 of
this Lease. Any Reimbursement relating to partial calendar years shall be
prorated accordingly. Tenant's Pro Rata Share of such Reimbursements shall be
based on the square footage of useable area contained in the Demised Premises in
proportion to the square footage of useable building area of the Property.
Tenant may audit or examine those items of expense in Landlord's records which
relate to Tenant's obligations under this Lease. Landlord shall promptly refund
to Tenant any overpayment which is established by an audit or examination. If
the audit or examination reveals an error of more than five percent (5%) over
the figures billed to Tenant, Landlord shall pay the reasonable cost of the
audit or examination.

D.    DEFINITIONS.

      1.    AD VALOREM TAXES. All general real estate taxes, general and special
assessments, parking surcharged, rent taxes, and other similar governmental
charges levied against the Property for each calendar year.

      2.    INSURANCE PREMIUMS. All Landlord's insurance premiums attributable
to the Property, including but not limited to insurance for fire, casualty,
general liability, property damage, medical expenses, and extended coverage, and
loss of rents coverage for six months' Rent.
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      3.    COMMON AREA MAINTENANCE EXPENSES. Common area maintenance expenses
("CAM") means all costs of maintenance, inspection and repairs of the common
areas of the Property, including but not limited to those costs for security,
lighting, painting, cleaning, decorations and fixtures, utilities, ice and snow
removal, trash disposal, project signs, minor roof defects, pest control,
project promotional expenses, property owners' association dues, wages and
salary costs of maintenance personnel, and other expenses benefiting all the
Property which may be incurred by Landlord, in its discretion, including sales
taxes and a reasonable service charge for the administration thereof. The
"common area" is defined as that part of the Property intended for the
collective use of all tenants including, but not limited to, the parking areas,
driveways, loading areas, landscaping, gutters and downspouts, plumbing,
electrical systems, roof, exterior walls, sidewalks, malls, promenades (enclosed
or otherwise), meeting rooms, doors, windows, corridors and public rest rooms.
CAM does not include depreciation on Landlord's original investment, cost of
tenant improvements, real estate brokers' fees, Landlord's management office and
overhead expenses, or interest or depreciation on capital investments.

      4.    OPERATING EXPENSES. All costs of ownership, building management,
maintenance, repairs and operation of the Property, including but not limited to
taxes, insurance, CAM, reasonable management fees, wages and salary costs of
building management personnel, overhead and operational costs of a management
office, janitorial, utilities, and professional services such as accounting and
legal fees. Operating Expenses do not include the capital cost of management
office equipment and furnishings, depreciation on Landlord's original
investment, roof and structural maintenance, the cost of tenant improvements,
real estate brokers' fees, advertising, or interest or depreciation on capital
investments.

      5.    ROOF AND STRUCTURAL MAINTENANCE EXPENSES. All costs of maintenance,
repair and replacement of the roof, roof deck, flashings, skylights, foundation,
floor slabs, structural components and the structural soundness of the building
in general.

      6.    BASE YEAR/EXPENSE STOP ADJUSTMENT. Tenant shall pay to Landlord as
additional rent Tenant's Pro Rata Share of increases in Landlord's Ad Valorem
Taxes, Insurance Premiums, CAM Expenses, Operating Expenses, and/or Roof and
Structural Maintenance Expenses, whichever are applicable, for the Property for
any calendar year during the Lease Term or during any Extension of this Lease,
over [CHECK ONLY ONE]:

      [ ]  a.  Such amounts paid by Landlord for the Base Year 2002 , or

      [ ]  b.  $N/A per square foot of floor area (as set forth in Section
               1.04.C) per year.

      7.    PRO RATA ADJUSTMENT. Tenant shall pay to Landlord as additional Rent
Tenant's Pro Rata Share of the total amount of Landlord's Ad Valorem Taxes,
Insurance Premiums, CAM, Operating Expenses, and/or Roof and Structural
Maintenance Expenses, whichever are applicable, for every calendar year during
the Lease Term and during any extension of this Lease.

      8.    FIXED AMOUNT ADJUSTMENT. Tenants shall pay to Landlord as additional
Rent the following monthly amounts as Tenant's Reimbursement to Landlord for the
applicable expenses which are incurred by or assessed against the Property:

          Ad Valorem Taxes                            $ N/A  per month
          Insurance Premiums                          $ N/A  per month
          CAM Expenses                                $ N/A  per month
          Operating Expenses                          $ N/A  per month
          Roof and Structural Maintenance Expenses    $ N/A  per month

      9.    NET LEASE PROVISIONS. Notwithstanding anything contained in this
Lease to the contrary in Article Seven or otherwise, Tenant shall be responsible
for paying Tenant's Pro Rata Share of all costs of ownership, maintenance,
repairs, replacements, and operation of the Demised Premises and the Property,
including but not limited to all costs of Ad Valorem Taxes, Insurance Premiums,
Common Area Maintenance Expenses, Operating Expenses, and Roof and Structural
Maintenance Expenses.
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E.    [ ]   GROSS-UP PROVISIONS. [CHECK THIS ONLY IF APPLICABLE.] If the
Property is a multi-tenant building and is not fully occupied during the Base
Year or any portion of the Lease Term, an adjustment shall be made in computing
the variable costs for each applicable calendar year. Variable costs shall
include only those items of expense that vary directly proportionately to the
occupancy of the Property. Variable costs which are included in the CAM and
Operating Expenses shall be increased proportionately to the amounts that, in
Landlord's reasonable judgment, would have been incurred had ninety percent
(90%) of the useable area of the Property been occupied during those years.
<PAGE>
                                  PAT HAGGERTY

               NORTH TEXAS COMMERCIAL ASSOCIATION OF REALTORS(R)

                              ADDENDUM B TO LEASE

                                RENEWAL OPTIONS

DEMISED PREMISES/ADDRESS: 15510 Wright Brothers Drive, Addison, Texas 75001

A.    OPTION TO EXTEND TERM. Landlord grants to Tenant one option(s) (the
"Option") to extend the Lease Term for an additional term of sixty months each
(the "Extension"), on the same terms, conditions and covenants set forth in this
Lease, except as provided below. Each Option may be exercised only by written
notice delivered to the Landlord no earlier than one hundred eighty ( 180 ) days
before, and no later than ninety ( 90 ) days before, the expiration of the Lease
Term or the preceding Extension of the Lease Term, whichever is applicable. If
Tenant fails to deliver Landlord written notice of the exercise of an Option
within the prescribed time period, such Option and any succeeding Options shall
lapse, and there shall be no further right to extend the Lease Term. Each Option
may only be exercised by Tenant on the express condition that, at the time of
the exercise, Tenant is not in default under any of the provisions of this
Lease. The foregoing Options are personal to Tenant and may not be exercised by
an assignee or subtenant without Landlord's written consent.

B.    CALCULATION OF RENT. The Base Rent during the Extension(s) shall be
determined by one of the following methods [CHECK ONE]:

[ ] 1. Consumer Price Index Adjustment. The monthly Base Rent during the
Extension shall be determined by multiplying the monthly installment of Base
Rent during the last month of the Lease Term by a fraction determined as
follows:

      a.    The numerator shall be the Latest Index which means either
            [CHECK ONE]:

            [ ] (1) the Index published for the nearest calendar month preceding
                    the first day of the Extension, or
            [ ] (2) the Index for the month of __________ preceding the
                    Extension.

      b.    The denominator shall be the Initial Index which means either
            [CHECK ONE]:

            [ ] (1) the Index published for the nearest calendar month preceding
                    the Commencement Date, or
            [ ] (2) the Index for the month of __________ preceding the
                    Commencement Date.

[IF NO BLANKS ARE FILLED IN ABOVE, THE CHOICE (1) INCLUDING THE PHRASE, "THE
NEAREST CALENDAR MONTH PRECEDING," SHALL APPLY.]

      c.    The Index means the Consumer Price Index (CPI) for All Urban
Consumers (All Items) U.S. City Average (unless this box is checked [ ] in which
case the CPI for the Dallas/Fort Worth Consolidated Metropolitan Statistical
Area shall be used) published by the U.S. Department of Labor, Bureau of Labor
Statistics (Base Index of 1982-84 = 100). If the Index is discontinued or
revised, the new index or computation which replaces the Index shall be used in
order to obtain substantially the same result as would have been obtained if it
had not been discontinued or revised. If such computation would reduce the Rent
for the particular Extension, it shall be disregarded, and the Rent during the
immediately preceding period shall apply instead.

[X] 2. FAIR MARKET RENTAL VALUE. The Base Rent during the Extension shall be the
Fair Market Rental determined as follows:

      a.    The "Fair Market Rental" of the Demised Premises means the price
that a ready and willing tenant would pay as of the commencement of the
Extension as monthly rent to a ready and willing landlord of demised premises
comparable to the Demised Premises if the property were exposed for lease on the
open market for a reasonable period of time, and taking into account the term of
the Extension, the amount of improvements made by Tenant at its expense, the
creditworthiness of the Tenant, and all of the purposes for which the property
may be used and not just the use proposed to be made of the Demised Premises by
Tenant. Upon proper written notice by Tenant to Landlord of Tenant's election to
exercise the renewal Option, Landlord shall within fifteen (15) days thereafter
<PAGE>
notify Tenant in writing of Landlord's proposed Fair Market Rental amount and
the Tenant shall thereupon notify Landlord of Tenant's acceptance or rejection
of Landlord's proposed amount. Failure of Tenant to reject Landlord's Fair
Market Rental amount within fifteen (15) days after receipt of Landlord's notice
shall be deemed Tenant's acceptance of Landlord's proposed Fair Market Rental
amount.

      b.    If Landlord and Tenant have not been able to agree on the Fair
Market Rental amount prior to the date the option is required to be exercised,
the rent for the Extension shall be determined as follows: Within thirty (30)
days following the exercise of the option, Landlord and Tenant shall endeavor in
good faith to agree upon a single Appraiser (defined below). If Landlord and
Tenant are unable to agree upon a single Appraiser within the thirty day period,
each shall then appoint one Appraiser by written notice to the other, given
within ten (10) days after the thirty day period. Within ten (10) days after the
two Appraisers are appointed, the two Appraisers shall appoint a third
Appraiser. If either Landlord or Tenant fails to appoint its Appraiser within
the prescribed time period the single Appraiser appointed shall determine the
Fair Market Rental amount of the Demised Premises. Each party shall bear the
cost of the appraiser appointed by it and the parties shall share equally the
cost of the third appraiser. The term "Appraiser" means a State Certified Real
Estate Appraiser licensed by the State of Texas to value commercial property.

      c.    The Fair Market Rental Value of the Demised Premises shall be the
average of two of the three appraisals which are closest in amount as described
below, and the third appraisal shall be disregarded. In no event shall the Rent
be reduced by reason of such computation. If the Fair Market Rental is not
determined prior to the commencement of the Extension, then Tenant shall
continue to pay to Landlord the Rent applicable to the Demised Premises
immediately prior to the Extension until the Fair Market Rental amount is
determined, and when it is determined, Tenant shall pay to Landlord within ten
(10) days after receipt of such notice the difference between the Rent actually
paid by Tenant to Landlord and the new Rent determined under this Lease.

[ ] C. FIXED RENTAL ADJUSTMENTS. The monthly Base Rent shall be increased
beginning on the following dates to these amounts:

       Date: February 1, 2004              Amount: $8,870.83
       Date: February 1, 2005              Amount: $8,870.83
       Date: February 1, 2006              Amount: $8,870.83
       Date: February 1, 2007              Amount: $8,870.83
<PAGE>
                              WRIGHT BROTHERS SITE

            15510 Wright Brothers Drive, Addison (Dallas), TX 75244

                              ADDENDUM H TO LEASE

                              ADDITION PROVISIONS

NOTE: TO THE EXTENT THIS ADDENDUM H CONFLICTS WITH THE TERMS OF THE LEASE, THIS
      ADDENDUM H SHALL CONTROL.

A.    LEASE TERM - EARLY TERMINATION OPTION

      Refer to Section 1.05, "Lease Term," and Article Two, "Lease and Lease
      Term."

      The term of the lease is five years. However, Landlord agrees to allow
      Tenant the option to terminate the Lease after three years for a fee equal
      to three months rent; i.e. $23,951.25. Tenant can only execute this option
      in writing on or before the third anniversary of the Commencement Date
      (June 1, 2005).

      Probex is offering a base rent of $5.00 / SF / Year; $8870.83 per month,
      $106,450 per year. The total Base Rent for the term of the lease is
      $479,025 = $106,450 x 5 - (6 x 8870.83 = 53,225)

B.    PERMITTED USE

      Refer to Section 6.01, "Permitted Use," and Article Fourteen,
      "Environmental Representation and Indemnity."

      Probex Corp. intends to relocate our laboratory, technical offices and
      headquarter offices to a common site in the North Dallas Area. Our
      laboratory will be conducting analytical and pilot scale process research
      to support development and improvement of our ProTerra(TM) technology for
      refining base lubricating oil and other products from a used motor oil
      feedstock. The City of Dallas has confirmed that our Laboratory facilities
      can be classified as a "Medical or Scientific Laboratory" and suitable for
      locating in an IR Industrial Research District per Chapter 51(A) of the
      "Dallas Development Code."

      The Probex laboratory facilities will include some small-scale storage and
      use of used lubricating oil (classified as non-hazardous and a Class 3B
      Combustible liquid), typical test and laboratory chemicals and solvents,
      and small quantities of sample products. Probex Corp. will provide MSDS
      sheets and an inventory

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File: Wright Bros Add H_Ro2.doc   Page 1 of 3              Rev.: R01 (25-Mar-02)
                                                                             ATT
<PAGE>
                                                            Wright Brothers Site
                                     Addendum H to Lease - Additional Provisions

      for review and approval by the Landlord. Per Section 14.02, Landlord's
      written consent of the storage and use of these materials is a prior
      condition of the Lease.

      Probex will apply for all required environmental, health and safety
      permits and approvals. This Lease Agreement is contingent on Probex's
      ability of obtain the required permits and approvals.

C.    COMPLIANCE WORK BY LANDLORD FOR EXISTING FACILITIES

      Refer to Section 6.02, "Compliance with Law."

D.    SUBLETTING

      Refer to Article Ten, "Assignment and Subletting."

      Landlord agrees to allow Tenant to Sublet the property to any appropriate
      Tenant without amending the Lease Agreement. Landlord agrees to grant
      consent to sublet all or part of the Demised Premises without unreasonable
      restriction. Landlord shall only deny consent for reasonable cause.

E.    MAKE-READY WORK BY LANDLORD (L) AND TENANT (T) AND TENANT

      Landlord agrees to perform the following work at its own expense:

      -     L     Conduct Asbestos Review as required by the Town of Addison for
                  the Certificate of Occupancy and abate asbestos found.

      -     T     Replace carpeting in the Executive Office Space, including
                  removal of platforms from the "Display Room." Carpeting to be
                  of equal or better quality to existing carpeting in new
                  condition. Tenant to approval carpet selection and color.

      -     T     Refinish paneling in Executive Office Space

      -     T     Add carpeting to the non-Executive office spaces as shown in
                  Exhibit "B"; cross-hatched areas. Carpeting to be of same
                  standard as that in Executive Office Space. Tenant to approval
                  carpet selection and color.

      -     T     Patch and paint walls of all non-paneled offices spaces,
                  including break-room, conference room and non-executive office
                  spaces

      -     T     Replace ceiling tiles and paint support frames as required in
                  all office spaces

      -     T     Repair lighting fixtures and replace bulbs as required

      -     T     Clean/repair tile flooring in non-executive office spaces

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File: Wright Bros Add H_Ro2.doc   Page 2 of 3              Rev.: R01 (25-Mar-02)
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<PAGE>
                                                            Wright Brothers Site
                                     Addendum H to Lease - Additional Provisions

      -     T     Repair/upgrade bathrooms, including replace fixtures (sinks,
                  toilets, etc.), repair and paint walls, replace floor
                  covering.

      -     L     Perform inspection of the HVAC system (determine mechanical
                  condition), and clean and sanitize HVAC system and ducts.
                  Remove mold as required.

      -     L     Clean & flush Warehouse area floor drains and sump system

            Note: New carpeting should not be installed until after build-out of
                  new offices by Tenant is complete.

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File: Wright Bros Add H_Ro2.doc   Page 3 of 3              Rev.: R01 (25-Mar-02)
                                                                             ATT

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