EXHIBIT 10.3

                            DEBT EXTENSION AGREEMENT

This Agreement is made and entered into as of this 1st day of November 2007, by
and between G. S. Beckwith Gilbert, of 35 Vista Drive, Greenwich, Connecticut
06830 ("Lender"), and MEGADATA CORPORATION, a New York corporation, with a
principal place of business at 35 Orville Drive, Bohemia, New York 11716
("Borrower" or "Megadata"):

                                   WITNESSETH


         WHEREAS, Megadata has issued promissory notes to Lender for value
received;


         WHEREAS, the total amount due and owing under the promissory notes and
accrued interest as of November 1, 2007 is $12,614,893; and


         WHEREAS, Lender and Megadata desire to modify certain terms and
conditions of the outstanding promissory notes as of the date of this Agreement
and issue a Replacement promissory note for value received upon the terms and
conditions set forth herein.


         NOW, THEREFORE, in consideration of the foregoing and the agreements
contained herein, the parties hereby agree as follows:

1.       MODIFICATION OF PREVIOUS NOTES:

         The outstanding promissory notes previously issued to Lender plus
accrued interest totaling $12,614,893 in aggregate principal amount shall be
modified as set forth herein.

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2.       ISSUANCE AND TERMS OF REPLACEMENT NOTE:

         For value received, Megadata shall issue a Replacement Note (the
"Replacement Note") to Lender in the aggregate principal amount of $12,614,893.
The Replacement Note will be in the form attached as Exhibit A hereto.

         TERM. The principal amount of the Replacement Note, together with any
               and all accrued and unpaid interest thereon, shall be paid in
               full on November 1, 2008.

         INTEREST. The Replacement Note shall bear interest on the unpaid
               principal amount, from the date of issuance until paid in full at
               the rate of 4.5% per annum.

3. MISCELLANEOUS.

         AMENDMENT AND MODIFICATION. This Agreement may be amended, modified and
               supplemented only by a written instrument signed by all of the
               parties hereto expressly stating that such instrument is intended
               to amend, modify or supplement this Agreement.

         ENTIRE AGREEMENT. This Agreement contains the entire agreement between
               the parties hereto with respect to the subject matter hereof and
               supersedes all prior agreements and understandings, oral or
               written, with respect to such matters.

         SEVERABILITY. If any provision of this Agreement shall be determined to
               be invalid or unenforceable under law, such determination shall
               not affect the validity or enforceability of the remaining
               provisions of this Agreement.

         GOVERNING LAW; JURISDICTION. This Agreement shall be governed by and
               construed in accordance with the laws of the State of New York,
               without regard to the conflicts of law rules of such state.

         COUNTERPARTS. This Agreement may be executed in one or more
               counterparts, each of which shall be deemed an original, and all
               of which shall constitute one and the same agreement and shall
               become effective when one or more counterparts have been signed
               by each of the parties and delivered to the other party, it being
               understood that both parties need not sign the same counterpart.

IN WITNESS WHEREOF, the parties hereto have executed this Agreement as of the
day and year written above.


                                  MEGADATA CORPORATION
                                  35 Orville Drive
                                  Bohemia, New York 11716



                                  By:    /S/ JAMES T. BARRY
                                     ------------------------------
                                  Name:  James T. Barry
                                  Title:  President and Chief Executive Officer



                                  By:    /S/ JEFFREY P. DEVANEY
                                  Name:  Jeffrey P. Devaney
                                  Title:  Chief Financial Officer


                                  LENDER
                                  G.S. Beckwith Gilbert
                                  35 Vista Drive
                                  Greenwich, Connecticut 06830



                                  By:    /S/ G.S. BECKWITH GILBERT
                                  Name:  G.S. Beckwith Gilbert

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                                                                       EXHIBIT A

                             SECURED PROMISSORY NOTE

$12,614,893                                             New York, New York
                                                        AS OF NOVEMBER 1, 2007

                  For value received, MEGADATA CORPORATION, a New York
corporation (hereinafter referred to as "Borrower"), hereby unconditionally
PROMISES TO PAY to the order of G.S. Beckwith Gilbert ("Lender"), or his
permitted assigns, to an account designated by Lender, in lawful money of the
United States of America and in immediately available funds, the principal sum
of twelve million six hundred fourteen thousand and eight hundred ninety three
dollars ($12,614,893) together with interest on the unpaid principal amount of
this note at the rate of 4.5% per annum.

                  The principal amount evidenced hereby will be repaid in full
on November 1, 2008. All accrued and unpaid interest hereunder as of November 1,
2008, shall be payable on such date.

                  Notwithstanding the foregoing, the principal amount of the
indebtedness evidenced hereby together with all accrued interest shall be
immediately due and payable upon written notice to Borrower from Lender upon the
happening of any of the following Events of Default:

                  Any representation or warranty in the Securities Purchase
         Agreement, dated September 18, 1996, between Borrower and Lender shall
         be untrue or incorrect in any material respect;

                  Any of the assets of Borrower shall be attached, seized,
         levied upon or subjected to a writ or distress warrant, or come within
         the possession of any receiver, trustee, custodian or assignee for the
         benefit of creditors of Borrower and shall remain unstayed or
         undismissed for thirty (30) consecutive days; or any person other than
         Borrower shall apply for the appointment of a receiver, trustee or
         custodian for any of the assets of Borrower and shall remain unstayed
         or undismissed for thirty (30) consecutive days; or Borrower shall have
         concealed, removed or permitted to be concealed or removed, any part of
         its property, with the intent to hinder, delay or defraud its creditors
         or any of them or made or suffered a transfer of any of its property or
         the incurring of an obligation which may be fraudulent under any
         bankruptcy, fraudulent conveyance or other similar law;

                  A case or proceeding shall have been commenced against
         Borrower in a court having competent jurisdiction seeking a decree or
         order in respect of Borrower (i) under title 11 of the United States
         Code, as now constituted or hereafter amended, or any other applicable
         federal, state or foreign bankruptcy or other similar law, (ii)
         appointing a custodian, receiver, liquidator, assignee, trustee or
         sequestrator (or similar official) of Borrower or of any substantial
         part of its properties, or (iii) ordering the winding-up or liquidation
         of the affairs of Borrower and such case or proceeding shall remain
         undismissed or unstayed for thirty (30) consecutive days or such court
         shall enter a decree or order granting the relief sought in such case
         or proceeding;

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                  Borrower shall (i) file a petition seeking relief under title
         11 of the United States Code, as now constituted or hereafter amended,
         or any other applicable federal, state or foreign bankruptcy or other
         similar law, (ii) consent to the institution of proceedings thereunder
         or to the filing of any such petition or to the appointment of or
         taking possession by a custodian, receiver, liquidator, assignee,
         trustee or sequestrator (or similar official) of Borrower or of any
         substantial part of its properties, (iii) fail generally to pay its
         debts as such debts become due, or (iv) take any corporate action in
         furtherance of any such action;

                  Final judgment or judgments (after the expiration of all times
         to appeal therefrom) for the payment of money in excess of $100,000 in
         the aggregate shall be rendered against Borrower and the same shall not
         be vacated, stayed, bonded, paid or discharged for a period of thirty
         (30) days; or

                  Any other event shall have occurred which would have a
         material adverse effect on Borrower or its assets or financial
         condition in Lender's reasonable judgment and Lender shall have given
         Borrower at least twenty (20) days notice thereof.

                  As security for any and all liabilities of the Borrower to
Lender, now existing or hereafter arising hereunder, or otherwise, Lender is
hereby given a lien upon and a security interest in any and all moneys or other
property (i.e., goods and merchandise, as well as any and all documents relative
thereto; also, funds, securities, chooses in action and any and all other forms
of property whether real, personal or mixed, and any right, title or interest of
the Borrower therein or thereto), and/or the proceeds thereof, including
(without limitation of the foregoing) that in safekeeping or in which Borrower
may have any interest. In the event of the happening of any one or more Events
of Default, Lender shall have all of the rights and remedies provided to a
secured party by the Uniform Commercial Code in effect in New York State at that
time and, in addition thereto, the Borrower further agrees that (1) in the event
that notice is necessary, written notice delivered to the Borrower at its
principal executive offices ten business days prior to the date of public sale
of the property subject to the lien and security interest created herein or
prior to the date after which private sale or any other disposition of said
property will be made shall constitute reasonable notice, but notice given in
any other reasonable manner or at any other reasonable time shall be sufficient,
(2) in the event of sale or other disposition of such property, Lender may apply
the proceeds of any such sale or disposition to the satisfaction of Lenders
reasonable attorneys' fees, legal expenses and other costs and expenses incurred
in connection with the retaking, holding, preparing for sale, and selling of the
property, and (3) without precluding any other methods of sale, the sale of
property shall have been made in a commercially reasonable manner if conducted
in conformity with reasonable commercial practices of banks disposing of similar
property.

                  Demand, presentment, protest and notice of nonpayment and
protest are hereby waived by Borrower.

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                  This Note has been executed, delivered and accepted in the
State of New York and shall be interpreted, governed by, and construed in
accordance with, the laws of the State of New York.


                                        MEGADATA CORPORATION



                                        By:    /S/ JEFFREY P. DEVANEY
                                               ----------------------
                                        Jeffrey P. Devaney
                                        Title:  Chief Financial Officer