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                                                                   EXHIBIT 10.20



                            REVOLVING PROMISSORY NOTE

                      INNOVATION TECHNOLOGY PARTNERS, L.LC.

$3,500,000.00                                                    June 19, 2000

         FOR VALUE RECEIVED, Innovation Technology Partners, L.L.C., a limited
liability company formed under the laws of the State of Delaware (the
"Borrower") whose mailing address is 5487 San Felipe, Suite 4545, Houston, Texas
77057 promises to pay to the order of Calton, Inc. (the "Lender"), at the office
of the Lender at 125 Half Mile Road, Suite 206, Red Bank, New Jersey 07701-6749,
or at such other place as the Lender may from time to time designate to the
Borrower in writing, the lesser of (i) the principal amount of Three Million
Five Hundred Thousand Dollars ($3,500,000) or (ii) the aggregate principal
amount of Advances made by the Lender to the Borrower pursuant to the terms,
conditions and provisions of this Revolving Promissory Note (this "Note"). The
Borrower hereby further promises to pay the order of the Lender principal and
interest on the unpaid principal amount hereof from time to time outstanding and
unpaid, at the interest rate hereinafter set forth, and in lawful money of the
United States of America, which shall at the time of payment be legal tender in
payment of all debts and dues, both public and private, on the dates hereinafter
set forth. All capitalized terms used in this Note shall have the meaning
ascribed to them herein.

         This Note shall bear interest at a per annum rate equal to the Prime
Rate plus one (1) percentage point. The interest rate shall be adjusted monthly
based upon the Prime Rate published on the last business day of each month
during the term of this Note. Interest shall be payable quarterly on the first
day of each calendar quarter with respect to interest accrued prior to such
date, with the first such interest payment being due October 1, 2000. Principal
and all unpaid interest shall be due and payable on the fourth anniversary of
the date of this Note; provided, however, that in the event that a Prepayment
Event shall occur, the Borrower, at Lender's election, shall prepay, on the date
that the Prepayment Event shall occur, the amount then outstanding under this
Note in an amount equal to the lesser of (i) the Net Proceeds related to such
Prepayment Event or (ii) the principal and interest then outstanding under this
Note.



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         This Note is a revolving note which shall entitle the Borrower to
borrow, repay and reborrow amounts upon the terms and conditions of this Note.
In no event shall Lender have any obligation to advance more than $3,500,000
pursuant to this Note or to advance any amounts after June 16, 2004. The
Borrower hereby authorizes the Lender to endorse on the grid attached as
Schedule 1 to this Note, an appropriate notation evidencing the date and amount
of each Advance made pursuant to this Note and the date and amount of each
payment or prepayment of principal thereof. Each such notation, in the absence
of manifest error, shall constitute prima facie evidence of and be conclusive as
to the outstanding principal amount of all Advances; PROVIDED, HOWEVER, that the
failure to make such endorsement shall not limit or otherwise affect the
obligations of the Borrower to the Lender under this Note.

         The Borrower may make prepayments of principal, interest, or principal
and interest at any time without penalty. Upon the occurrence of an Event of
Default, the Borrower agrees that the Lender shall have all the rights and
remedies set forth in this Note, including, without limitation, the rights of
acceleration set forth herein.

         The Borrower may cancel this Note and terminate the provisions hereof
at any time by (1) paying all sums then payable hereunder and (2) notifying the
Lender that this Note is terminated.

               ARTICLE 1: EVENTS OF DEFAULT; RIGHTS AND REMEDIES

         1.1 EVENTS OF DEFAULT. The occurrence of any of the following events
(each, an "Event of Default") shall terminate any obligation on the part of the
Lender to disburse Loan Proceeds and, upon written notice from the Lender to the
Borrower, make this Note and the entire Indebtedness immediately due and payable
(PROVIDED, HOWEVER, that in the case of an Event of Default under Subsection (c)
all amounts owing under this Note shall automatically and immediately become due
and payable without any action by or on behalf of the Lender):

                  (a) Failure of the Borrower to pay within ten (10) days of the
date when due, whether by acceleration or otherwise, any of the Indebtedness in
accordance with this Note.

                  (b) The failure of Borrower to pay when due, or failure of
Borrower to perform or observe any other obligation or condition with respect to
any of the following obligations to any Person, beyond any period of grace under
the instrument creating such obligation if such failure would have a material
adverse effect on the financial condition of Borrower: (i) any indebtedness for
borrowed money or for the deferred purchase price of property in an amount in
excess of $100,000, (ii) any obligations under leases which have or should have
been characterized as capitalized leases, as determined in accordance with GAAP
in an amount in excess of $100,000, or (iii) any contingent liabilities, such as
guaranties, for the obligations of others relating to indebtedness for borrowed
money or for the deferred purchase price of property or relating to obligations
under leases which have or should have been characterized as capitalized leases,
as determined in accordance with GAAP in an amount in excess of $100,000.
Notwithstanding the foregoing, the Borrower will not be deemed to be in default
under this subparagraph if and so long as the Borrower contests in good faith
the validity or amount of any asserted claims and diligently prosecutes or
defends an action appropriate to obtain a binding determination of the disputed
matter and such contest shall have the effect of preventing the sale or
forfeiture of any property of the Borrower or any interest of the Borrower or
the Lender therein.

                  (c) The Borrower applies for or consents to the appointment of
a trustee or receiver for any part of its respective properties; any bankruptcy,
reorganization, debt arrangement, dissolution, or liquidation proceeding is
commenced or consented to by the Borrower, or any application for appointment of
a receiver or a trustee, or any proceeding for bankruptcy, reorganization, debt
management, or liquidation is filed for or commenced against the Borrower, and
is not withdrawn or dismissed within sixty (60) days thereafter.




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                  (d) Any lien for labor, services, materials, or otherwise
relating to an obligation of $100,000 or more is filed against any property of
the Borrower or any interest of the Borrower or the Lender therein and is not
removed within thirty (30) days thereafter; PROVIDED, HOWEVER, the Borrower will
not be deemed to be in default under this subparagraph if and so long as the
Borrower contests in good faith the validity or amount of any asserted lien and
diligently prosecutes or defends an action appropriate to obtain a binding
determination of the disputed matter and such contest shall have the effect of
preventing the sale or forfeiture of any property of the Borrower or any
interest of the Borrower or the Lender therein.

                  (e) Failure of Buyer to comply with the provisions of Article
2 of this Note.

                  (f) Any money judgment, writ or warrant of attachment or
similar process involving in an individual case or in the aggregate at any time
an amount in excess of $50,000 (not adequately covered by insurance) shall be
entered or filed against Borrower or its assets and shall remain undischarged,
unvacated or unstayed for a period of 60 days.

                  (g) Failure of the Borrower to comply with any other provision
of this Note not constituting an Event of Default under any of the preceding
provisions of this Section 1.1, and such failure continues for thirty (30) days
after notice to the Borrower from the Lender.

                  (h) The employment of any of Richard Dole, James West or
Frederick Huttner (each "an Employee") is terminated for any reason unless
Lender approves the individual replacing such Employee (it being acknowledged
and agreed that such approval shall not be unreasonably withheld and that the
Borrower shall have 90 days to identify an acceptable replacement).

         1.2 NO ADVANCES. The Lender shall have no obligation to make an Advance
if an Event of Default shall occur and be continuing.

         1.3 RIGHTS AND REMEDIES. In addition to the remedies set forth above,
upon the occurrence of an Event of Default, and until cured (provided such cure
is effected prior to the Lender giving the Borrower written notice of the
election by the Lender to accelerate all amounts owing under this Note on
account of such Event of Default), the Lender shall be entitled to exercise all
the rights and remedies provided by any applicable law, including, without
limitation, the Uniform Commercial Code as enacted in the State of New Jersey.
Each and every right or remedy granted to the Lender pursuant to this Note, or
allowed the Lender by law or equity, shall be cumulative. Failure or delay on
the part of the Lender to exercise any such right or remedy shall not operate as
a waiver thereof. Any single or partial exercise by the Lender of any such right
or remedy shall not preclude any future exercise thereof or the exercise of any
other right or remedy.

                      ARTICLE 2: COVENANTS OF THE BORROWER

         From and after the date of this Note and until the Indebtedness is
indefeasibly paid, in full, in cash, and this Note terminated, the Borrower
agrees that it will observe and comply with the following covenants for the
benefit of the Lender.



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         2.1 USE OF LOAN PROCEEDS. The Loan Proceeds shall be utilized by
Borrower for general working capital requirements and investments, as presented
in the Business Plan. Borrower shall furnish Lender with such detailed
documentation and information regarding Borrower's working capital requirements
and investments as Lender may request while this Note is outstanding.

         2.2 FUTURE DEBT. Borrower will not issue, incur, create, assume,
guarantee or otherwise become liable for any other indebtedness for borrowed
money unless such other indebtedness is for equipment, capital leasing items or
similar items used in the ordinary course of business of the Borrower and such
indebtedness is secured only by the equipment or items which are acquired with
the proceeds of the borrowed money.

         2.3 REPURCHASE OF INTEREST. Borrower will not repurchase any interests
in, or units representing interests in, Borrower from any member or unit holder
(except Lender), or make a return of capital to any member or unit holder
(except Lender), without the Lender's written consentwhile this Note is
outstanding.

         2.4 EXTRAORDINARY TRANSACTIONS. Borrower will not be a party to any
merger, consolidation, dissolution, redomestication or reorganization, or sell
or otherwise dispose of all or substantially all of its assets while this Note
is outstanding unless Borrower obtains the prior written consent of Lender.

                       ARTICLE 3: CONDITIONS TO ADVANCES

         3.1 CONDITIONS TO LOAN. Lender's obligation to make an Advance and to
disburse any of the Loan Proceeds is subject to each of the following conditions
precedent:

                  3.1.1 LOAN DOCUMENTS; OTHER DOCUMENTS. The Lender shall have
received a duly executed original of this Note, and such other instruments and
documents contemplated herein, as appropriate.

                  3.1.2 EVIDENCE OF ENTITY ACTION. The Lender shall have
received, if it so requests, in form and substance reasonably satisfactory to
the Lender, documents, including a resolution of its Board of Managers certified
by an officer of the Borrower evidencing all action taken by the Borrower to
authorize the execution, delivery and performance of this Note, and to make a
request for an Advance under this Note.

                  3.1.3 FURTHER ASSURANCES. The Borrower shall have provided
and/or executed and delivered to the Lender, in form and substance reasonably
satisfactory to the Lender, such further documents and instruments as the Lender
may in the Lender's discretion reasonably request.

                  3.1.4 ADVANCE REQUEST. Should Borrower at any time wish to
request the disbursement of any Loan Proceeds from Lender, the Borrower shall
deliver to the Lender, no later than three (3) Business Days preceding the
requested disbursement date, a written request (an "Advance Request"), in form
and substance reasonably satisfactory to the Lender, stating the dollar amount
of the requested Advance, the specific purpose for which the Advance is being




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requested and such details respecting the intended utilization of the Advance as
Lender may require. Provided that all other conditions of this Article 3 are
fulfilled, Lender shall make an Advance as requested. In the event that Lender
determines not to make an Advance as requested, Lender shall deliver to Borrower
within 48 hours of receiving such request a written notice stating the reason(s)
for Lender's determination prior to the requested disbursement date for the
Advance Lender determined not to make.

                  3.1.5 DEFAULT. No Event of Default shall have occurred and be
continuing, nor shall an Event of Default result from the making of the Advance.

                  3.1.6 MATERIAL ADVERSE CHANGE. There shall have been no
material adverse change in the business, financial condition or operating
results of the Borrower.

                  3.1.7 CHANGE OF CONTROL. Lender shall not own less than a 36%
equity interest in Borrower.

                               ARTICLE 4: NOTICES

         All notices, requests, and demands required or permitted under the
terms of this Note shall be in writing and shall be (a) addressed as set forth
below, or to such other address as a party may have specified by notice given to
the other party pursuant to this provision, and (b) deemed to have been given or
made: (i) if delivered personally, immediately upon delivery; (ii) if by telex,
telegram or facsimile transmission, immediately upon sending and upon
confirmation of receipt; (iii) if by nationally recognized overnight courier
service with instructions to deliver the next Business Day, one (1) Business Day
after sending; and (iv) if by United States Mail, certified mail, return receipt
requested, five (5) days after mailing.

                IF TO THE BORROWER:
                Innovation Technology Partners, L.L.C.
                5847 San Felipe, Suite 4545
                Houston, Texas  77057
                Fax No.:  (713) 914-9655
                Attention:  Managing Member

                WITH A COPY TO:
                Drew R. Fuller, Jr., Esq.
                Cauthorn Hale Hornberger Fuller Sheehan
                   Becker & Beiter Incorporated
                700 North Mary's Street, Suite 600
                San Antonio, Texas  78205
                Fax No.  (210) 271-1730

                IF TO THE LENDER TO:
                Calton, Inc.
                125 Half Mile Road
                Suite 206
                Red Bank, New Jersey  07701-6749
                Fax No.:  (732)  212-1290
                Attention:  Anthony J. Caldarone, President




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                WITH A COPY TO:
                Philip D. Forlenza, Esq.
                Giordano, Halleran & Ciesla, P.C.
                125 Half Mile Road
                P.O. Box 190
                Middletown, New Jersey  07748
                Fax No.:  (732) 224-6599

                             ARTICLE 5: DEFINITIONS

         As used herein, the following terms have the following meanings:

         5.1 "ADVANCE" means a disbursement of Loan Proceeds from Lender to
Borrower.

         5.2 "BUSINESS DAY" means any day other than a Saturday or Sunday and
other than a day which is a Federal legal holiday or a legal holiday for banks
in the State of New Jersey.

         5.3 "BUSINESS PLAN" means the Business Plan of the Company dated May
25, 2000.

         5.4 "INDEBTEDNESS" means all amounts due and owing under this Note.

         5.5 "LOAN PROCEEDS" means the proceeds of a revolving credit loan which
Lender hereby agrees to make available to the Borrower from time to time subject
to the terms, conditions and provisions of this Note in an amount which shall
not exceed in the aggregate at any time outstanding $3,500,000.

         5.6 "NET PROCEEDS" means all cash proceeds, less reasonable transaction
costs and, in the case of a sale of assets, after repayment of any indebtedness
secured by a lien on the assets sold that is required to be repaid upon sale.

         5.7 "PERSON" means any individual, corporation, association,
partnership, trust, organization, government, governmental agency, or other
entity.

         5.8 "PREPAYMENT EVENT" means (i) the incurrence by the Company or any
subsidiary of any indebtedness for borrowed money, except as permitted by
Section 2.2, (ii) the sale by the Company of any interest in the Company or any
subsidiary entity of the Company for cash or (iii) the sale by the Company or
any subsidiary entity of any asset, other than in the ordinary course of
business.

         5.9 "PRIME RATE" means the prime rate as published in the "Money Rates"
column of the Wall Street Journal.

                            ARTICLE 6: MISCELLANEOUS

         6.1 GOVERNING LAW. This Note shall be governed by and construed in
accordance with the applicable Laws of the State of New Jersey and the United
States of America from time to time in effect, without giving effect to any
otherwise applicable rules concerning conflicts of laws.




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         6.2 LITIGATION; JURISDICTION. Borrower irrevocably agrees that any
litigation with respect to this Note or enforcement of any judgment obtained
against Borrower for breach of this Note may be brought in the courts of the
State of New Jersey and in the United States District Court for the District of
New Jersey (collectively, the "specified courts") (if applicable subject matter
jurisdictional requirements are present), as Lender may elect; and, by execution
and delivery of this Note, Borrower irrevocably submits to such jurisdiction.
Borrower agrees that it shall maintain a duly appointed agent for service of
summons and other legal process as long as Borrower remains obligated under this
Note and shall keep Lender advised in writing of the identity and location of
such agent. The receipt by such agent and/or by Borrower of such summons or
other legal process in any such litigation shall be deemed personal service and
acceptance by Borrower for all purposes of such litigation. Borrower agrees that
a final judgment in any such action or proceeding shall be conclusive and may be
enforced in other jurisdictions by suit on the judgment or in any other manner
provided by law.

         6.3 CERTAIN WAIVERS. The Borrower and any sureties or endorsers hereof
hereby jointly and severally waive presentment for payment, demand, protest,
diligence in collection, and notice of dishonor and nonpayment of this Note, and
all defenses on the ground of delay, suretyship, release of any party liable for
payment hereof, or of any extension of time for the payment hereof (including
any right to notice of any of the foregoing) which may be hereafter given by the
holder of this Note from time to time to them or to anyone who has assumed the
payment of this Note, and it is specifically agreed that the obligations of said
Borrower, sureties or endorsers shall not be in any way affected or altered to
the prejudice of the holder hereof by reason of the assumption of payment of the
same by any other Person.

         6.4 COSTS OF COLLECTION. Borrower agrees to pay all reasonable costs of
collection, including reasonable attorneys' fees paid or incurred by Lender in
enforcing this Note on default or the rights and remedies herein provided.

         6.5 SUCCESSORS AND ASSIGNS. Except as otherwise expressly provided
herein, the provisions hereof shall inure to the benefit of, and be binding
upon, the successors and assigns of the parties hereto; PROVIDED, HOWEVER, that
the Borrower may not assign its rights and obligations hereunder. Any assignment
in contravention of this Section 6.5 shall be void.

         6.6 SEVERABILITY. In the event that one or more provisions of this Note
shall for any reason be held to be invalid, illegal or unenforceable in any
respect, such invalidity, illegality or unenforceability shall not affect any
other provisions of this Note, but this Note shall be construed as if such
invalid, illegal or unenforceable provision had never been contained herein.

         6.7 HEADINGS. The headings contained herein are for the purpose of
convenience of reference only and are not intended to be considered in
construing this Note.

         6.8 AMENDMENTS. Modifications and amendments of this Note may be made
solely in writing by the prior written consent of both the Borrower and the
holder of this Note.

         6.9 NON-NEGOTIABLE. This Note is not negotiable by Lender without
Borrower's prior written consent; provided however, that Lender may assign and
transfer this Note to a direct or indirect majority-owned subsidiary without
Borrower's consent.



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         IN WITNESS WHEREOF, the Borrower and Lender have executed this
Revolving Promissory Note this 16th day of June, 2000.

ATTEST:                                Innovation Technology Partners, L.L.C.



                                    By:
-----------------------                 ---------------------------------------
Name:                                   Name:
Title:                                  Title:




ATTEST:                                Calton, Inc.



                                    By:
-----------------------                 ---------------------------------------
Name:                                   Name:
Title:                                  Title:





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                          SCHEDULE 1 TO REVOLVING NOTE
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