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                                                                Exhibit 10.33.2

                              AMENDED AND RESTATED
                                 PROMISSORY NOTE

$3,500,000.00                   Houston, Texas                    June 26, 2002

         SCALABLE SOFTWARE, INC., a Delaware corporation (hereinafter called
"Maker") jointly and severally, For Value Received, promises and agrees to pay
as herein provided, unto the order of NEON SYSTEMS, INC., a Delaware corporation
(hereinafter called "Payee"), at its offices at 14100 Southwest Freeway, Suite
500, Sugar Land, Texas 77478, in lawful money of the United States of America
the principal sum of THREE MILLION FIVE HUNDRED THOUSAND AND NO/100 DOLLARS
($3,500,000.00), together with interest on the unpaid principal balance
outstanding from time to time hereon computed from the "Option Term Expiration
Date" (as hereinafter defined) until maturity at a varying interest rate per
annum which is two percent (2%) per annum (hereinafter called the "Margin
Percentage") above the "Prime Rate" (as hereinafter defined), but in no event to
exceed the maximum rate of nonusurious interest allowed from time to time by law
(hereinafter called the "Highest Lawful Rate"), with adjustments in such varying
rate to be made on the same date as any change in the Prime Rate and adjustments
due to changes in the Highest Lawful Rate to be made on the effective date of
any change in the Highest Lawful Rate. Interest shall be calculated on the basis
of a year of 365 or 366 days, as the case may be, and the actual number of days
elapsed (including the first day but excluding the last day) occurring in the
period for which such interest is payable. Certain capitalized terms used herein
as definitions are defined herein beginning on page three of this note.

         ALL PAST due principal and interest shall bear interest until paid at a
varying rate per annum, which is two percent (2%) per annum plus the Margin
Percentage plus the Prime Rate (but in no event to exceed the Highest Lawful
Rate). The amount of interest to accrue at the rate specified in the preceding
sentence, having due consideration for the period during which such rate is in
effect, shall be calculated in accordance with the provisions of the immediately
preceding paragraph of this note, except that for such purpose the references to
the "Margin Percentage" shall be deemed to be references to two percent (2%) per
annum in excess of the Margin Percentage.

         ALL PRINCIPAL and accrued and unpaid interest on this note shall be due
and payable on June 26, 2005.

         PAYMENT of this note before maturity may be made at any time or from
time to time, in whole or in part, without penalty or premium. Any such payment
shall be applied first to accrued interest and secondly to principal.

         IF ANY PAYMENT of principal or interest on this note shall become due
on a day that is not a day on which commercial banks are open for business in
the State of Texas, such payment shall be made on the next succeeding day on
which commercial banks are open for business in the State of Texas, unless the
effect of such extension would be to carry the payment over to the

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next calendar month, in which event such payment shall be due on the preceding
day on which commercial banks are open for business in the State of Texas, and
any such extension or reduction of time shall in such case be included in
computing interest in connection with such payment.

         IF AN EVENT OF DEFAULT (as hereinafter defined) occurs which is
continuing, the owner and holder of this note may, without notice or demand
(both of which are expressly waived by Maker), declare all sums owing hereon at
once due and payable. If default is made in the payment of this note at maturity
(regardless of how its maturity may be brought about), and the same is placed in
the hands of an attorney for collection, or suit is filed hereon, or proceedings
are had in bankruptcy, probate, receivership or other judicial proceedings for
the establishment or collection of any amount called for hereunder, or any
amount payable or to be payable hereunder is collected through any such
proceedings, Maker agrees and is also to pay to the owner and holder of this
note a reasonable amount as attorney's or collection fees.

         MAKER REPRESENTS and warrants to Payee that (a) the execution, delivery
and performance of this note and any other instrument or document executed in
connection with or as security for this note, are within Maker's powers, and
will not contravene any law or any agreement or undertaking to which it is a
party or by which it is bound, (b) this note is a legal, binding obligation of
Maker, enforceable against Maker in accordance with its terms, (c) there are no
claims pending, or to Maker's knowledge threatened, which, if adversely
determined, would have a material adverse effect on the financial condition of
Maker, and (d) no authorization or consent of, and no filing or registration
with, any court, governmental authority or third party is or will be necessary
for the execution, delivery or performance by Maker of this note and any other
instrument or document executed in connection with or as security for this note.

         MAKER AGREES with Payee that, so long as any amount, whether principal
or interest, remains unpaid on this note, Maker (a) will not sell, lease,
assign, transfer or otherwise dispose of all or substantially all of its assets,
or enter into any agreement (verbal or written) to do so, other than as
contemplated by the Agreement and Plan of Merger or in any other agreement
permitted by the Agreement and Plan of Merger; (b) will deliver to Payee (i) as
soon as available and in any event within 30 days after the end of each calendar
month the income statement of Maker for the immediately preceding calendar month
and for the period from the beginning of the respective calendar year to the end
of such month, and (ii) the balance sheet of Maker as of the end of the
immediately preceding calendar month, (c) will deliver, or cause to be
delivered, to Payee duly executed and completed original counterparts of each
Guaranty Agreement, and (d) shall perform, observe and comply with all
covenants, agreements and terms contained in the Agreement and Plan of Merger
required to be performed, observed or complied with by it.

         MAKER, co-makers, signers, sureties, endorsers and guarantors, and each
of them, expressly waive demand and presentment for payment, notice of
nonpayment, protest, notice of protest, notice of dishonor, notice of intent to
accelerate the maturity hereof, notice of the acceleration of the maturity
hereof, bringing of suit and diligence in taking any action to collect

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amounts called for hereunder and in the handling of securities at any time
existing in connection herewith; and are and shall be jointly, severally,
directly and primarily liable for the payment of all sums owing and to be owing
hereon, regardless of and without any notice, diligence, act or omission as or
with respect to the collection of any amount called for hereunder or in
connection with any right, lien, interest or property at any and all times had
or existing as security for any amount called for hereunder.

         IT IS the intention of Maker and Payee to conform strictly to
applicable usury laws. Accordingly, if the transactions contemplated hereby
would be usurious under applicable law (including the laws of the State of Texas
and the laws of the United States of America), then, in that event,
notwithstanding anything to the contrary herein or in any agreement entered into
in connection with or as security for this note, it is agreed as follows: (i)
the aggregate of all consideration which constitutes interest under applicable
law that is taken, reserved, contracted for, charged or received under this note
or under any of the other aforesaid agreements or otherwise in connection with
this note shall under no circumstances exceed the maximum amount of interest
allowed by applicable law, and any excess shall be cancelled automatically and,
if theretofore paid, shall be credited on the note by the holder hereof (or, to
the extent that this note shall have been or would thereby be paid in full,
refunded to the Maker); and (ii) in the event that maturity of this note is
accelerated by reason of an election by the holder hereof resulting from any
default hereunder or otherwise, or in the event of any required or permitted
prepayment, then such consideration that constitutes interest may never include
more than the maximum amount allowed by applicable law, and excess interest, if
any, provided for in this note or otherwise shall be cancelled automatically as
of the date of such acceleration or prepayment and, if theretofore paid, shall
be credited on this note (or, to the extent that this note shall have been or
would thereby be paid in full, refunded to the Maker).

         AS USED in this note, the following terms shall have the respective
meanings indicated below:

                  "Agreement and Plan of Merger" means that certain Agreement
                   ----------------------------
         and Plan of Merger dated June 26, 2002, between Maker, Payee and
         certain stockholders of Maker, as the same may be amended,
         supplemented or modified from time to time.

                  "Change of Control" means any change in the ownership of 50%
                   -----------------
         or more of the shares of stock of Maker or voting power of such stock
         (other than among the current shareholders of Maker on the date
         hereof).

                  "Event of Default" each of the following shall constitute and
                   ----------------
         be deemed an "Event of Default":

                  (a)      Maker shall fail to pay this note, whether principal
         or interest, when due.

                  (b)      Any representation or warranty made or deemed made by
         Maker or any of its respective officers in any certificate, report,
         notice, or financial statement furnished at any time in connection
         with this note or any other instrument or document executed in

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         connection with or as security for this note shall be false,
         misleading, or erroneous in any material respect when made or deemed
         to have been made.

                  (c)      Maker shall fail to perform, observe, or comply with
         any covenant, agreement or term contained in this note, for a period
         of five (5) days following the date on which Payee gives Make notice
         of such failure.

                  (d)      Maker shall commence a voluntary proceeding seeking
         liquidation, reorganization, or other relief with respect to itself or
         its debts under any bankruptcy, insolvency, or other similar law now
         or hereafter in effect or seeking the appointment of a trustee,
         receiver, liquidator, custodian, or other similar official of it or a
         substantial part of its property or shall consent to any such relief
         or to the appointment of or taking possession by any such official in
         an involuntary case or other proceeding commenced against it or shall
         make a general assignment for the benefit of creditors or shall take
         any corporate action to authorize any of the foregoing.

                  (e)      An involuntary proceeding shall be commenced against
         Maker seeking liquidation, reorganization, or other relief with
         respect to it or its debts under any bankruptcy, insolvency, or other
         similar law now or hereafter in effect or seeking the appointment of a
         trustee, receiver, liquidator, custodian or other similar official for
         it or a substantial part of its property, and such involuntary
         proceeding shall remain undismissed and unstayed for a period of
         thirty (30) days.

                  (f)      Maker shall fail to pay when due any amount owing on
         any of its other debt (including, without limitation, debt under the
         Senior Note), or the maturity of any such debt shall have been
         accelerated, or any such debt shall have been required to be prepaid
         prior to the stated maturity thereof, or any event shall have occurred
         that permits (or, with the giving of notice or lapse of time or both,
         would permit) any holder or holders of such debt or any person acting
         on behalf of such holder or holders to accelerate the maturity thereof
         or require any such prepayment.

                  (g)      This note or any other instrument or document
         executed by Maker in connection with or as security for this note
         shall at any time and for any reason cease to be in full force and
         effect or shall be declared null and void or the validity or
         enforceability thereof shall be contested or challenged by Maker, or
         Maker shall deny that it has any further liability or obligation
         hereunder prior to payment in full of all obligations hereunder.

                  (h)      A Change of Control shall occur.

                  (i)      One of the following shall occur: 1) the Maker shall
         approve or resolve to approve any Acquisition Proposal; or 2) the
         consummation of any Acquisition Proposal.

                  (j)      The Guaranty Agreement shall at any time after its
         execution and delivery and for any reason cease to be in full force
         and effect or shall be declared null and void or

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         the validity or enforceability thereof shall be contested or
         challenged by any Guarantor party thereto, or any Guarantor shall deny
         it has any further liability or obligation thereunder or shall fail to
         perform its obligations thereunder.

                  "Existing Note" means that certain Amended and Restated
                   -------------
         Promissory Note dated November 14, 2001, in the principal amount of
         $3,500,000 executed by Maker and payable to the order of Payee as
         therein provided, as extended by Extension Agreement dated as of March
         31, 2002, between Maker and Payee.

                  "Guarantors" means, jointly and severally, Louis R. Woodhill,
                   ----------
         James R. Woodhill, John Moores, and any other Person who may execute a
         Guaranty Agreement.

                  "Guaranty Agreement" means the written guaranty agreement
                   ------------------
         executed by each Guarantor, jointly and severally guaranteeing prompt
         payment of all principal owing on this note, together with interest and
         expenses as set forth in said Guaranty Agreement.

                  "Option" means the option granted by Maker to Payee under the
                   ------
         terms and conditions of the Agreement and Plan of Merger.

                  "Option Term Expiration Date" means the date which is two (2)
                   ---------------------------
         years after the date of the Agreement and Plan of Merger, if Payee does
         not exercise the Option on or before such date.

                  "Prime Rate" means the variable rate of interest per annum
                   ----------
         established by JPMorgan Chase Bank from time to time as its prime rate
         which shall vary from time to time. Such rate is set by JPMorgan Chase
         Bank as a general reference rate of interest, taking into account such
         factors as JPMorgan Chase Bank may deem appropriate, it being
         understood that many of JPMorgan Chase Bank's commercial or other loans
         are priced in relation to such rate, that it is not necessarily the
         lowest or best rate charged to any customer and that JPMorgan Chase
         Bank may make various commercial or other loans at rates of interest
         having no relationship to such rate.

                  "Senior Note" means that certain promissory note dated of even
                   -----------
         date herewith, in the original principal amount of $5,500,000 executed
         by Maker and payable to the order of Payee as therein provided,
         together with any and all renewals, extensions for any period,
         rearrangements or modifications thereof.

         THIS NOTE represents a renewal, extension, rearrangement and
modification of the outstanding principal balance owing on the Existing Note.

         MAKER AGREES that the payment of all amounts owing or to be owing under
or in connection with this note shall be subordinate to all amounts owing under
or in connection with the Senior Note, whether outstanding on the date hereof or
hereafter incurred.

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         THIS NOTE EMBODIES THE FINAL, ENTIRE AGREEMENT BETWEEN MAKER AND PAYEE
WITH RESPECT TO THE SUBJECT MATTER HEREOF AND SUPERSEDE ANY AND ALL PRIOR
COMMITMENTS, AGREEMENTS, REPRESENTATIONS, AND UNDERSTANDINGS, WHETHER WRITTEN OR
ORAL, RELATING TO THE SUBJECT MATTER HEREOF AND THEREOF AND MAY NOT BE
CONTRADICTED OR VARIED BY EVIDENCE OF PRIOR, CONTEMPORANEOUS, OR SUBSEQUENT ORAL
AGREEMENTS OR DISCUSSIONS OF MAKER AND PAYEE. THERE ARE NOT ORAL AGREEMENT
BETWEEN MAKER AND PAYEE.

MAKER:                   SCALABLE SOFTWARE, INC.

                         By:     ______________________________________________
                         Name:   ______________________________________________
                         Title:  ______________________________________________

PAYEE:                   NEON SYSTEMS, INC.

                         By:     ______________________________________________
                         Name:   ______________________________________________
                         Title:  ______________________________________________

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