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                                                                    EXHIBIT 10.1

PROMISSORY NOTE


U.S. $10,000,000.00
     --------------

December 20, 1999 New York, New York
-----------

1.     OBLIGATION AND REPAYMENT: For value received, Borrower absolutely and
       unconditionally promises to pay to the order of the Bank, at the Office,
       without defense, setoff or counterclaim, the principal amount of Ten
       Million and 00/100 United States Dollars, together with interest and any
       other sum(s) due as specified below. The principal amount of this Note
       shall be due and payable as follows (complete one of the following as
       applicable):

       (A)    [ ] ON DEMAND.

       (B)    On November 30, 2000; and

       (C)    In consecutive installments, of which each but the last shall be
              $_____________ and the last of which shall be equal to the then
              unpaid principal balance of this Note. The first such installment
              shall be due on ______________, 19__. Each subsequent installment
              shall be due on the corresponding day of each month/ quarter/
              other __________ thereafter (or if there is no such corresponding
              day, on the last day of such period). The remaining principal
              balance shall be due on ______________, 19__.

       (D)    [X] In accordance with the attached Rider.

2.     INTEREST: Subject to paragraph A(2) of the Terms and Conditions, interest
       shall accrue on the principal amount of this Note outstanding from time
       to time at the following rate (the "Loan Rate") (complete one of the
       following as applicable):

       (A)    A fixed rate equal to ______% per year.

       (B)    A Variable Prime-Based Rate equal to the Prime Rate plus ______%
              per year.

       (C)    [X] In accordance with the attached Rider.

       Interest shall be payable monthly/ quarterly/ (other) _____________ and
       at any Payment Date and at any time that any part of the principal or any
       installment of this Note is paid.

3.     RIDERS: IN THE EVENT OF ANY INCONSISTENCY BETWEEN THIS NOTE AND ANY
       RIDER(S) TO WHICH THIS NOTE IS SUBJECT, THE PROVISIONS OF SUCH RIDER(S)
       SHALL PREVAIL. THIS NOTE IS SUBJECT TO ANY RIDER(S) REFERRED TO IN
       PARAGRAPH 1(D) AND/OR 2(C) AND TO THE FOLLOWING RIDER(S), ALL OF WHICH
       ARE PART OF THIS NOTE:

                  Multiple-Loan Rider to Promissory Note
                  --------------------------------------
                           (Libor-Based Rate)

4.     ADDRESS AND IDENTIFICATION OF BORROWER:

       Address:   800 Regency Parkway
               ---------------------------------------------------------
                  Cary, NC  27511
               ---------------------------------------------------------
       Telex or similar number:
                               -----------------------------------------
       Answerback:
                  ------------------------------------------------------
       Telecopy or similar number:
                                  --------------------------------------
       Social Security or Taxpayer ID number:
                                             ---------------------------

5.     AGREEMENT TO ALL TERMS AND CONDITION; AUTHORIZATION TO COMPLETE BLANKS:
       THIS NOTE IS SUBJECT TO THE TERMS AND CONDITIONS SET FORTH BELOW AND ON
       THE REVERSE SIDE OF THIS NOTE. EACH OF THE UNDERSIGNED AGREES TO ALL OF
       THE PROVISIONS OF THIS NOTE, INCLUDING THE TERMS AND CONDITIONS AND ANY
       RIDER(S). THE BANK IS AUTHORIZED TO COMPLETE ANY BLANK SPACE IN THIS
       NOTE. SUCH COMPLETION SHALL BE CONCLUSIVE, FINAL AND BINDING ON BORROWER
       IN THE ABSENCE OF MANIFEST ERROR.

6.     NO REPRESENTATIONS OR AGREEMENTS BY THE BANK: EACH OF THE UNDERSIGNED
       ACKNOWLEDGES THAT THE BANK HAS MADE NO REPRESENTATION, COVENANT,
       COMMITMENT OR AGREEMENT TO BORROWER EXCEPT PURSUANT TO ANY WRITTEN
       DOCUMENT EXECUTED BY THE BANK.

7.     NO REPRESENTATION OF NONENFORCEMENT: EACH OF THE UNDERSIGNED ACKNOWLEDGES
       THAT NO REPRESENTATIVE OR AGENT OF THE BANK HAS REPRESENTED OR INDICATED
       THAT THE BANK WILL NOT ENFORCE ANY PROVISION OF THIS NOTE, INCLUDING THE
       TERMS AND CONDITIONS AND ANY RIDER(S), IN THE EVENT OF LITIGATION OR
       OTHERWISE.

8.     WAIVER OF JURY TRIAL: BORROWER WAIVES, AND UNDERSTANDS THAT THE BANK
       WAIVES, THE RIGHT TO A JURY TRIAL WITH RESPECT TO ANY DISPUTE ARISING
       HEREUNDER OR RELATING TO ANY OF THE LIABILITIES; ANY JUDICIAL PROCEEDING
       WITH RESPECT TO ANY SUCH DISPUTE SHALL TAKE PLACE WITHOUT A JURY.

9.     EXECUTION OF PROMISSORY NOTE:

       Print name of Borrower: Level 8 Systems, Inc.
                               -------------------------------------------------
       (Signature) By:        /s/ Steven Dmiszewicki
                      ----------------------------------------------------------
       Print name:            Steven Dmiszewicki
                      ----------------------------------------------------------
       Title or capacity:     President
                         -------------------------------------------------------
       (if signing on behalf of Borrower)
       (Signature) By:        /s/ Dennis McKinnie
                      ----------------------------------------------------------
       Print Name:            Dennis McKinnie
                      ----------------------------------------------------------
       Title or capacity:     SVP, Secretary
                         -------------------------------------------------------
       (if signing on behalf of Borrower)

================================================================================

                              TERMS AND CONDITIONS

Definitions are set forth in paragraph M

A.     CALCULATION AND ACCRUAL OF INTEREST: (1) GENERALITY. Interest shall be
       calculated on a daily basis on outstanding balances at the Applicable
       Rate, divided by 360, on the actual days elapsed. During any time that
       the Applicable Rate would exceed the applicable maximum lawful rate of
       interest, the Applicable Rate shall automatically be reduced to such
       maximum rate. Any interest payment made in excess of such maximum rate
       shall be applied as, and deemed to be, in the Bank's sole discretion, (a)
       a payment of any of the Liabilities, in such manner as determined by the
       Bank, or (b) cash collateral to be retained by the Bank to secure
       repayment of this Note. (2) INCREASED RATE. Interest shall accrue at the
       Increased Rate upon and after (a) the occurrence of any Debtor Relief
       Action, (b) any demand of payment of this Note (if payable on demand) or
       (c) the occurrence of any Event of Default (if this Note is payable other
       than on demand). (3) ACCRUAL. To the extent permitted by Law, interest
       shall accrue at the Applicable Rate on all unpaid Liabilities under this
       Note, including but not limited to any unpaid interest and any unpaid
       obligation owed pursuant to paragraph B (Indemnification).

B.     INDEMNIFICATION: To the extent permitted by Law: (1) TAXES: All payments
       under this Note shall be made free and clear of, and without deduction
       for, any Taxes. If Borrower shall be required to deduct any Taxes in
       respect of any sum payable under this Note, then (a) the sum payable
       shall be increased so that the Bank shall receive an amount equal to the
       sum the Bank would have received had no deductions been made, and (b)
       Borrower shall make such deductions and shall pay the amount deducted to
       the relevant Governmental Authority. Borrower shall pay to the Bank on
       demand, and shall indemnify and hold the Bank harmless from, any and all
       Taxes paid by the Bank and any and all liability (including penalties,
       interest and expenses) with respect thereto, whether or not such Taxes
       were correctly or legally asserted. Within 30 days after any Taxes are
       paid, Borrower shall furnish evidence thereof to the Bank. (2) REGULATORY
       COSTS. In the event that in connection

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       with the transaction(s), contemplated by this Note and/or the Bank's
       funding of such transaction(s), the Bank is required to incur any
       Regulatory Costs in order to comply with any Law issued after the date of
       this Note, then Borrower shall pay the Bank on demand, and shall
       indemnify and hold the Bank harmless from any and all such Regulatory
       Costs. (3) COSTS AND EXPENSES. Borrower shall pay the Bank on demand, and
       shall indemnify and hold the Bank harmless from, any and all costs and
       expenses. (4) PREPAYMENT COSTS. If Borrower makes any payment of Prepaid
       Principal (voluntarily or not), and if the Applicable Rate with respect
       to such Prepaid Principal is not a Variable Prime-Based Rate, then
       Borrower shall pay to the Bank an amount sufficient to compensate the
       Bank for its Prepayment Costs. Borrower acknowledges that determining the
       actual amount of Prepayment Costs may be difficult or impossible in any
       specific instance. Accordingly, Borrower agrees that Prepayment Costs
       shall be deemed to be the excess, if any, of (i) the product of (A) the
       Prepaid Principle, times (B) the Applicable Rate divided by 360, times
       (C) the remaining number of days from the date of the payment to the
       applicable Payment Date, over (ii) that amount of interest which the Bank
       determines that the holder of a Treasury Obligation selected by the Bank
       in the amount (or as close to such amount as feasible) of the Prepaid
       Principal and having a maturity date on (or as soon after as feasible)
       the applicable Payment Date would earn if that Treasury Obligation were
       purchased in the secondary market on the date the Prepaid Principal is
       paid to the Bank and were held to maturity. Borrower agrees that the
       determination of Prepayment Costs shall be based on amounts which a
       holder of a Treasury Obligation could receive under these circumstances,
       whether or not the Bank actually invests the Prepaid Principal in any
       Treasury Obligation. (5) BANK CERTIFICATE. The Bank's certificate as to
       any amounts owing under this paragraph shall be prima facia evidence of
       Borrower's obligation.

C.     SET OFF: Every Account of Borrower with the Bank shall be subject to a
       lien and to being set off against the Liabilities. The Bank may at any
       time at its option and without notice, except as may be required by law,
       charge and/or appropriate and apply all or any part of any such Account
       toward the payment of any of the Liabilities.

D.     EVENTS OF DEFAULT: The remainder of this paragraph D shall not apply if
       this Note is payable on demand. Each of the following shall be an Event
       of Default hereunder: (1) NONPAYMENT. (a) The nonpayment when due of any
       part of the Liabilities; (b) the prohibition by any Law of payment of any
       part of any of the Liabilities; (2) BANKRUPTCY; ADVERSE PROCEEDINGS. (a)
       The occurrence of any Debtor Relief Action; (b) the appointment of a
       receiver, trustee, committee, custodian, personal representative or
       similar official for any Party or for any Material part of any Party's
       property; (c) any action taken by any Party to authorize or consent to
       any action set forth in subparagraph D(2)(a) or (b); (d) the rendering
       against any Party of one or more judgments, orders, decrees and/or
       arbitration awards (whether for the payment of money or injunctive or
       other relief) which in the aggregate are Material to such Party, if they
       continue in effect for 30 days without being vacated, discharged, stayed,
       satisfied or performed; (e) the issuance or filing of any warrant,
       process, order of attachment, garnishment or other lien or levy against
       any Material part of any Party's property; (f) the commencement of any
       proceeding under, or the use of any of the provisions of any Law against
       any Material part of any Party's property, including but not limited to
       any Law (i) relating to the enforcement of judgments or (ii) providing
       for forfeiture to, or condemnation, appropriation, seizure or taking
       possession by, or on order of any Governmental Authority; (g) the
       forfeiture to, or the condemnation, appropriation, seizure or taking
       possession by, or on the order of, any Governmental Authority, of any
       Material part of any Party's property; (h) any Party being charged with a
       crime by indictment, information or the like. (3) NONCOMPLIANCE. (a) Any
       Default with respect to any Agreement with or to the Bank, (b) the giving
       to the Bank by or on behalf of any Party at any time of any materially
       incorrect or incomplete representation, warranty, statement or
       information; (c) the failure of any Party to furnish to the Bank, copies
       of its financial statements and such other information respecting its
       business, properties, condition or operations, financial or otherwise,
       promptly when, and in such form as, reasonably required or requested by
       the Bank; (d) any Party's failure or refusal, upon reasonable notice from
       the Bank, to permit the Bank's representative(s) to visit such Party's
       premises during normal business hours and to examine and make
       photographs, copies and extracts of such Party's property and of its
       books and records; (e) any Party's concealing, removing or permitting to
       be concealed or removed, any part of its property with the intent to
       hinder or defraud any of its creditors; (f) any Party's making or
       suffering any Transfer of any of its property, which Transfer is deemed
       fraudulent under the law of any applicable jurisdiction; (g) the
       revocation or early termination of any Party's obligations under any
       Agreement with or to the Bank (including, but not limited to any of the
       Liabilities) or the validity, binding effect or enforceability of any
       such obligations being challenged or questioned, whether or not by the
       institution of proceedings. (4) ADVERSE CHANGES. (a) the occurrence of a
       Material adverse change in any Party's financial condition; (b) the death
       or incompetence (if a person) or the dissolution or liquidation (if a
       corporation, partnership or other entity) of any Party or such Party's
       failure to be and remain in good standing and qualified to do business in
       each jurisdiction Material to such Party; (c) any Material Default with
       respect to any Material Agreement other than with or to the Bank; (d) any
       Default pursuant to which any Person shall have the power to effect an
       Acceleration of any Material Debt; (e) any Acceleration or demand of
       payment with respect to any Material Debt; (f) any Party's becoming
       insolvent, as defined in the Uniform Commercial Code; (g) the Bank's
       believing in good faith that the prospect of payment of any of the
       Liabilities or of performance of any other obligation of any Party to the
       Bank is impaired; (h) the Material suspension of any Party's business;
       (i) any Party's Material failure to pay any tax when due; (j) the
       expulsion of any Party from any exchange or self-regulatory organization
       or any loss, suspension, nonrenewal or invalidity of any Party's Material
       license, permit, franchise, patent, copyright, trademark or the like; (k)
       the occurrence of any event which gives any Person the right to assert a
       lien, levy or right of forfeiture against any Material part of any
       Party's property; (l) Borrower's failure to give the Bank notice, within
       10 Business Days after Borrower had notice or knowledge, of the
       occurrence of any event which, with the giving of notice and/or lapse of
       time, would constitute an Event of Default. (5) BUSINESS CHANGES. (a) any
       change in Control of any Party; (b) any merger or consolidation involving
       any Party; (c) any Party's sale or other Transfer or substantially all of
       its property; (d) any bulk sale by any Party; (e) any Material change in
       the nature or structure of any Party's business. (6) EXCHANGE CONTROLS.
       (a) Any Party's failure to obtain any Exchange Control Permit deemed by
       the Bank to be necessary or appropriate; (b) the failure to obtain the
       renewal of any such Exchange Control Permit at least 30 days prior to its
       expiration.

E.     REMEDIES: (1) ACCELERATION AT BANK'S OPTION. Upon any failure to pay this
       Note in full on demand (if payable on demand) or (if this Note is payable
       other than on demand) upon the occurrence of any Event


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       of Default other than any Debtor Relief Action, then any and all
       Liabilities, not then due, shall, at the Bank's option, become
       immediately due and payable without notice, which Borrower waives. (2)
       AUTOMATIC ACCELERATION. Upon the occurrence of any Debtor Relief Action,
       then, whether or not any of the Liabilities are payable upon demand and
       notwithstanding paragraph F, any and all Liabilities, not then due, shall
       automatically become immediately due and payable without notice or
       demand, which Borrower waives. (3) Additional Remedies. The Bank shall
       have all rights and remedies available to it under any applicable
       Agreement or Law.

F.     WAIVER OF PROTEST, ETC.: Notice, presentment, protest, notice of dishonor
       and except for such of the Liabilities as are payable on demand, but
       subject to subparagraph E(2) demand for payment are hereby waived as to
       all of the Liabilities.

G.     PAYMENT: (1) MANNER. Any payment by other than immediately available
       funds shall be subject to collection, interest shall continue to accrue
       until the funds by which payment is made are available to the Bank. If
       and to the extent any payment of any of the Liabilities is not made when
       due, the Bank is authorized in its discretion to effect payment by
       charging any amount so due against any Account of Borrower with the Bank
       without notice, except as may be required by law, whether or not such
       charge creates an overdraft. (2) Application. Any payment received by the
       Bank (including a deemed payment under paragraph A, a set-off under
       paragraph C or a charge against an Account under this paragraph G) shall
       be applied to pay any obligation of indemnification (including but not
       limited to under paragraph B) and to pay any other Liabilities (including
       interest thereon and the principal thereof) in such order as the Bank
       shall elect in its discretion. Borrower will continue to be liable for
       any deficiency. (3) PREPAYMENT. Borrower shall be entitled to pay any
       outstanding principal amount or installment under this Note on any
       Business Day prior to the applicable Payment Date without the prior
       consent of the Bank provided that (a) any such payment shall be together
       with payment of all Liabilities then due and all interest accrued on the
       Prepaid Principal to the date of such payment, and (b) if the Applicable
       Rate with respect to such Prepaid Principal is not a Variable Prime-Based
       Rate, any such payment shall be on not less than 5 Business Day's notice
       to the Bank and shall be accompanied by any amount required pursuant to
       subparagraph B(4). Any such payment shall, unless otherwise consented to
       by the Bank, be applied pro rata to the last outstanding principal
       amount(s) to become due under this Note in inverse order of maturity. (4)
       NON-BUSINESS DAYS. If any payment of any of the Liabilities is due on any
       day that is not a Business Day, it shall be payable on the next Business
       Day. The additional day(s) shall be included in the compilation of
       interest. (5) EXTENSION AT BANK'S OPTION. The Bank shall have the option,
       which may be exercise one or more times by notice(s) to Borrower, to
       extend the date on which any amount is payable hereunder to one or more
       subsequent date(s) set forth in such notice(s).

H.     PARTIES; NO TRANSFER BY BORROWER: If Borrower is more than one Person,
       all of them shall be jointly and severally liable under the Note. The
       obligations under this Note shall continue in force and shall apply
       notwithstanding any change in the membership of any partnership executing
       this Note, whether arising from the death or retirement of one or more
       partners or the accession of one or more new partners. Without the Bank's
       written consent, Borrower shall have no right to make any Transfer of any
       of the Liabilities, any such purported Transfer shall be void. Subject to
       the foregoing, the provisions of this Note shall be binding on Borrower's
       executors, administrators, successors and assigns.

I.     BANK TRANSFERS: (1) TRANSFERABILITY. Without limiting the Bank's rights
       hereunder, the Bank may make a Transfer of all or any part of (a) any
       obligation of Borrower to the Bank (including but not limited to any of
       the Liabilities); (b) any obligation of any other Party in connection
       with any of the Liabilities; (c) any Agreement of any Party in connection
       with any of the Liabilities; (d) any collateral, mortgage, lien or
       security interest, however denominated, securing any of the Liabilities;
       and/or (e) the Bank's rights and, if any, obligations with respect to any
       of the foregoing. (2) EXTENT OF TRANSFER. In the event the Bank shall
       make any Transfer of any of the foregoing items ("Transferred Items"),
       then - to the extent provided by the Bank with respect to such Transfer,
       the Transferee shall have the rights, powers, privileges and remedies of
       the Bank. The Bank shall thereafter, to the extent of such Transfer, be
       forever relieved and fully discharged from all liability or
       responsibility, if any, that it may have to any Person with respect
       thereto, except for claims, if any, arising prior to or upon such
       Transfer. The Bank shall retain all its rights and powers with respect to
       any Transferred items to the extent that it has not made a Transfer
       thereof. Without limiting the foregoing, to the extent of any such
       Transfer, paragraph B (indemnification) shall apply to any Taxes,
       Regulatory Costs, Costs and Expenses and Prepayment Costs of, or incurred
       by, any Transferee, and paragraphs C (Set-Off) and G(1) (Payment-Manner)
       shall apply to any Account of Borrower with any Transferee. (3)
       DISCLOSURES. The Bank is authorized to disclose to any prospective or
       actual Transferee any information that the Bank may have or acquire about
       Borrower and any information about any other Person submitted to the Bank
       by or on behalf of Borrower. (4) NEGOTIABILITY DEFENSES WAIVED. IF THIS
       NOTE IS NOT A NEGOTIABLE INSTRUMENT, BORROWER WAIVES ALL DEFENSES (EXCEPT
       SUCH DEFENSES AS MAY BE ASSERTED AGAINST A HOLDER IN DUE COURSE OF A
       NEGOTIABLE INSTRUMENT) WHICH BORROWER MAY HAVE OR ACQUIRE AGAINST ANY
       TRANSFEREE WHO TAKES THIS NOTE, OR ANY COMPLETE OR PARTIAL INTEREST IN
       IT, FOR VALUE, IN GOOD FAITH AND WITHOUT NOTICE THAT IT IS OVERDUE OR HAS
       BEEN DISHONORED OR OF ANY DEFENSE AGAINST OR CLAIM TO IT ON THE PART OF
       ANY PERSON.

J.     NO ORAL CHANGES; NO WAIVER BY THE BANK; PARTIAL UNENFORCEABILITY. This
       Note may not be changed orally. Neither a waiver by the Bank of any of
       its options, powers or rights in one or more instances, nor any delay on
       the part of the Bank in exercising any of them, nor any partial or single
       exercise thereof, shall constitute a waiver thereof in any other
       instance. Any provision of this Note which is prohibited, unenforceable
       or not authorized in any jurisdiction shall, as to such jurisdiction, be
       ineffective to the extent of such prohibition, unenforceability or
       non-authorization, without invalidating the remaining provisions of the
       Note in that or any other jurisdiction and without affecting the
       validity, enforceability or legality of such provision in any other
       jurisdiction.

K.     DISPUTES AND LITIGATION: (1) GOVERNING LAW. This Note and the rights and
       obligations of the Bank and Borrower hereunder shall be governed by the
       internal laws of the State of New York without giving effect to conflict
       of laws principles. (2) JURISDICTION, VENUES AND SERVICE OF PROCESS.
       Borrower submits to the nonexclusive jurisdiction of the federal and
       state courts in the State of New York in New York County with respect to
       any dispute that may be made on Borrower by personal deliver at, or by
       mail addressed to, any address to which the Bank is authorized to address
       notices to Borrower. (3) WAIVER OF DEFENSES, SETOFFS, COUNTERCLAIMS AND
       CERTAIN DAMAGES. Borrower waives the right to assert any defense, setoff
       or counterclaim in any proceeding relating in any way to this Note or any
       transaction contemplated hereby. The Bank shall not have any liability
       for negligence,


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       except solely to the extent required by law and not disclaimable, and
       except for its own gross negligence or willful misconduct. In any event,
       the Bank shall not have any liability for any special, consequential or
       punitive damages. (4) SOVEREIGN IMMUNITY. Borrower irrevocably waives,
       with respect to itself and its property, any sovereign immunity that it
       may have or hereafter acquire, including but not limited to immunity from
       the jurisdiction of any court, from any legal process, from attachment
       prior to judgment, from attachment in aid of execution, from execution or
       otherwise.

L.     NOTICE. Any notice in connection with any of the Liabilities shall be in
       writing and may be delivered personally or by cable, telex, telecopy or
       other electronic means of communication, or by certified mail, return
       receipt requested, addressed (a) to Borrower as set forth herein or to
       any other address that the Bank believes to be Borrower's address, and
       (b) to the Bank at Bank Hapoalim B.M., 1177 Avenue of the Americas, New
       York, New York 10036, Attention Legal Department. Any such notices shall
       be addressed to such other address(es) as may be designated in writing
       hereafter. All such notices shall be deemed given when delivered
       personally or electronically or when mailed, except notice of change of
       address, which shall be deemed to have been given when received.

M.     DEFINITIONS. The following definitions apply in this Note: (1)
       ACCELERATION. Any acceleration of payment of requirement of prepayment of
       any Debt, or any Debt's becoming due and payable prior to stated
       maturity. (2) ACCOUNT: (a) the balance of any account of Borrower with
       any Person, (b) any claim of Borrower against any Person and/or (c) any
       property in the possession or custody of, or in transit to, any Person,
       whether for safekeeping, collection, pledge or otherwise, as to which
       Borrower has any right, power or interest, in each case whether existing
       now or hereafter, in any jurisdiction worldwide, and whether or not
       disconnected in the same currency as any of the Liabilities. (3)
       AGREEMENT. Any agreement or instrument (including but not limited to this
       Note), no matter when made, under which any Party is obligated to any
       Person. (4) APPLICABLE RATE. Whichever of the Loan Rate or Increased Rate
       is the applicable interest rate at any time. (5) BANK: Bank Hapoalim B.M.
       (6) BORROWER. The Person(s) executing this Note at paragraph 9 or any one
       or more of them. "Borrower" may refer to one or more Persons. (7)
       BUSINESS DAY. Any day on which both (a) banks are regularly open for
       business in New York City and (b) the Office is open for ordinary
       business in the Bank's discretion, the Office may be closed on any
       Saturday, Sunday, legal holiday or other day on which it is lawfully
       permitted to close. (8) CONTROL. The power, alone or in conjunction with
       others, directly or indirectly, through voting securities, by contract or
       otherwise, to direct or cause the direction of a Person's management and
       policies. (9) COSTS AND EXPENSES. Any and all reasonable costs and
       expenses (including but not limited to attorneys' fees and disbursements)
       incurred in connection with the Borrower and/or the Liabilities,
       including but not limited to those for (a) any action taken, whether or
       not by litigation, to collect, or to protect rights or interests with
       respect to, or to preserve any collateral securing, any of the
       Liabilities; (b) compliance with any legal process or any order or
       directive of any Governmental Authority with respect to any party; (c)
       any litigation or administrative proceeding relating to any Party and/or
       (d) any amendment, modification, extension or waiver with respect to any
       of the Liabilities. (10) DEBT. Any Party's obligation of any sort (in
       whole or in part for the payment of money to any Person, whether (a)
       absolute or contingent, (b) secured or unsecured, (c) joint, several or
       independent, (d) nor or hereafter existing, or (e) due or to become due.
       (11) DEBTOR RELIEF ACTION. The commencement by any Party or (unless
       dismissed or terminated within 30 days) against any Party of any
       proceeding under any law of any jurisdiction (domestic or foreign)
       relating to bankruptcy, reorganization, insolvency, arrangement,
       composition, receivership, liquidation, dissolution, moratorium or other
       relief of financially distressed debtors, or the making by any Party of
       any assignment for the benefit of creditors. (12) DEFAULT. Any breach,
       default or event of default under, or any failure to comply with, any
       provision of any Agreement. (13) EVENT OF DEFAULT. Any event set forth in
       paragraph D. (14) EXCHANGE CONTROL PERMIT. Any permit or license issued
       by a Governmental Authority outside the United States under which any
       Party is permitted (a) to incur and pay any of the Liabilities in the
       United States in any currency(ies) in which denominated or (b) to enter
       into, incur and, or perform any other obligation or Agreement. (15)
       GOVERNMENTAL AUTHORITY. Any domestic or foreign, national or local (a)
       government, (b) governmental, quasi-governmental or regulatory agency or
       authority, (c) court or (d) central bank or other monetary authority.
       (16) INCREASED RATE. (a) If the Loan Rate is a Variable Prime-Based Rate,
       the Increased Rate with respect to the entire outstanding principal
       balance shall be the Loan Rate plus 2% per year; (b) if the Loan Rate is
       not a Variable Prime-Based Rate, the Increased Rate with respect to any
       amount of principal or installment shall be (i) the Loan Rate plus 2% per
       year prior to the applicable Payment Date and (ii) the Prime Rate plus 4%
       per year on or subsequent to the applicable Payment Date. (17) LAW. Any
       treaty, law, regulation, rule, Judgment, order, decree, guideline,
       interpretation or request (whether or not having the force of law) issued
       by any Governmental Authority. (18) LIABILITIES. (a) any and all of the
       Debt evidenced by this Note, and any and all other Debt of Borrower to,
       or held or to be held by, the Bank in any jurisdiction worldwide for its
       own account or as agent for another or others, whether created directly
       or acquired by Transfer or otherwise, and (b) any and all obligations of
       any other Party with respect to any of such Debt. (19) LOAN RATE. The
       interest rate determined under paragraph 2. (20) MATERIAL. Material to
       the business or financial condition of any Party on a consolidated or
       consolidating basis. (21) OFFICE. The Bank's office at 1177 Avenue of the
       Americas, New York, New York 10036, or such other place as the Bank may
       specify by notice. (22) PARTY. (a) borrower; (b) any maker co-maker or
       endorser or any Agreement evidencing or any guarantor surety,
       accommodation party or indemnitor with respect to, or any Person that
       provides any collateral as security for, or any Person that issues a
       subordination, comfort letter, standby letter of credit, repurchase
       agreement, put agreement, option, other Agreement or other credit support
       with respect to any of the Liabilities; (c) if any Party is a partnership
       or joint venture, any general partner or joint venturer in such Party,
       and (d) any Person (i) that is under the Control of any Party and (ii)
       whose business or financial condition is Material to such Party. (23)
       PAYMENT DATE. Any Business Day on which any part of the principal or any
       installment of this Note becomes due and payable under paragraph 1 (and
       not on account of an Acceleration). (24) PERSON. Any person, partnership,
       joint venture, company, corporation, uncorporated organization or
       association, trust, estate, Governmental Authority, or any other entity.
       (25) PREPAID PRINCIPAL. Any amount of principal or any installment of
       this Note which Borrower pays prior to the applicable Payment Date for
       such amount. (26) PREPAYMENT COSTS. All losses, costs and expenses
       incurred as a result of receiving Prepaid Principal and of reinvesting it
       at rate(s) which may be less than the Applicable Rate


                                       4
<PAGE>   5

       for such Prepaid Principal. (27) PRIME RATE. The Bank's New York Branch's
       stated Prime Rate as reflected in the books and records as such Prime
       Rate may change from time to time. The Bank's determination of its Prime
       Rate shall be conclusive and final. The Prime Rate is a reference rate
       and not necessarily the lowest interest rate charged by the Bank. (28)
       REGULATORY COSTS. Any and all costs and expenses of complying with any
       Law, including but not limited to with respect to (a) any reserves or
       special deposits maintained for or with, or pledges to, any Governmental
       Authority, or (b) any capital, capital equivalency ledger account, ratio
       of assets to liabilities, risk-based capital assessment or any other
       capital substitute, risk-based or otherwise. (29) Taxes. Any and all
       present and future taxes, levies, imposts, deductions, charges and
       withholdings in any jurisdiction worldwide, and all liabilities with
       respect thereto, which are imposed with respect to this Note or to any
       amount payable under this Note, excluding taxes determined on the basis
       of the net income of a Person or of any of its offices. (30) TRANSFER.
       Any negotiation, assignment, participation, conveyance, grant of a
       security interest, lease, delegation, or any other direct or indirect
       transfer of a complete or partial, legal, beneficial, economic or other
       interest or obligation. (31) TRANSFEREE. Any Person to whom a Transfer is
       made. (32) TRANSFERRED ITEMS. Items defined in paragraph I. (33) TREASURY
       OBLIGATIONS. A note, bill or bond issued by the United States Treasury
       Department as a full faith and credit general obligation of the United
       States. (34) VARIABLE PRIME-BASED RATE. Any Applicable Rate which is
       determined based on the Prime Rate. Any such rate shall change
       automatically when and as the Prime Rate changes.


                                       5
<PAGE>   6

                     Multiple-Loan Rider to Promissory Note

                               (Libor-Based Rate)

This Rider is referred to in paragraph 2(c) of, and constitutes a part of, a
note of Borrower to the Bank dated December 20, 1999.

===============================================================================

SPECIFIC TERMS

(a)  Margin:  1.00% per year

(b)  Interest Period:  (__) _________ days [x] 1, 2 or 3 months and [x] as
                       agreed from time to time

(c)  Minimum Draw Amount:  U.S. $500,000.00              [  ]  None
                                ----------------

(d)  Minimum Multiple Amount: U.S. $                     [  ]  None
                                    ------------

===============================================================================

Borrower agrees to the above Specific Terms and to all of the Terms and
Conditioning set forth below.

Print Borrower's Name:    Level 8 Systems, Inc.
                        ------------------------------------------------------

<TABLE>
<S>                                                 <C>
(Signature) By: /s/ Steven Dmiszewicki              (Signature) By: /s/ Dennis McKinnie
               ------------------------                            ---------------------
Print Name and Title:  Steven Dmiszewicki, Pres.    Print Name and title: Dennis McKinnie, SVP
                     ---------------------------                          --------------------
</TABLE>

TERMS AND CONDITIONS

Certain capitalized terms are defined in paragraph 4.

1.     Advances. Borrower may receive a Loan in any principal amount upon
       Borrower's request to the Bank and the Bank's agreement thereto, subject
       to all of the following conditions:

       (a)    Agreement of the Bank and Borrower. Subject to subparagraphs 1(b),
              1(c) and 2(b), the Bank and Borrower shall have agreed, not later
              than the Determination Time, with respect to the Loan's (i)
              principal amount, (ii) LIBOR-Base Rate and (iii) Interest Period;
              provided, however, that if the Bank determines that by such
              Determination Time, Borrower has failed or declined to agree on
              the LIBOR-Based Rate and/or Interest Period with respect to such
              Outstanding Principal Amount, then interest on such Outstanding
              Principal Amount shall accrue at the LIBOR-Based Rate without the
              agreement of Borrower, and the Interest Period shall be of the
              same duration as


<PAGE>   7

              the Interest Period just ended with respect to such Outstanding
              Principal Amount or, if there was no such prior Interest Period,
              one month.

       (b)    Applicable limitations. (i) The applicable Payment Date shall not
              be later than the Due Date; (ii) the total of the Outstanding
              Principal Amounts of all Loans shall not exceed the principal
              amount set forth in the Note; (iii) the principal amount of any
              single Loan request shall be not less than any Minimum Draw Amount
              set forth under Specific Terms; and (iv) the principal amount of
              any single Loan request shall be an integral multiple of any
              Minimum Multiple Amount set forth under Specific Terms.

       (c)    Borrower's request and agreement. Borrower's request for a Loan
              and Borrower's agreement to the terms thereof shall be
              communicated to the Bank in any form that is acceptable in each
              instance to the Bank in its sole discretion, which may include
              telephone, telex, telecopy or a writing executed by Borrower.
              Borrower shall have provided the Bank with documentation,
              satisfactory in form and substance to the Bank in its sole
              discretion, confirming the authority of the person(s) agreeing to
              such terms on behalf of Borrower.

2.     Payment of Principal and Interest. Subject to the other provisions of the
       Note:

       (a)    Obligation and Time of Repayment. Each Outstanding Principal
              Amount shall be due and payable at the applicable Payment Date.

       (b)    Loan Rate. Interest on any Outstanding Principal Amount shall
              accrue at the LIBOR-Based Rate; provided, however, that if the
              Bank determines (i) that by the Determination Time (A) by reason
              of circumstances affecting the London Interbank Market generally,
              adequate and fair means do not exist for ascertaining an
              applicable LIBOR rate or it is impractical for the Bank to fund or
              continue to fund the Outstanding Principal Amount during the
              applicable Interest Period, or (B) quotes for funds in United
              States Dollars in sufficient amounts comparable to the relevant
              Outstanding Principal Amount and for the duration of the
              applicable Interest Period would not be available to the Bank in
              the London Interbank Market, or (C) quotes for funds in United
              States Dollars in the London Interbank Market will not accurately
              reflect the cost to the Bank of making a Loan or of funding the
              relevant Outstanding Principal Amount during the applicable
              Interest Period, or (ii) that at any time the making or funding of
              loans, or charging of interest at rates, based on LIBOR shall be
              unlawful or unenforceable for any reason, then as long as such
              circumstance(s) shall continue, interest on the relevant
              Outstanding Principal Amount shall accrue at the Alternate Rate.

       (c)    Payment and Calculation of Interest. Interest shall be payable (i)
              at each Payment Date or (whenever the Applicable Rate is a
              variable Prime-Based Rate) monthly, (ii) at the Due Date and (iii)
              at any time that any Outstanding Principal Amount or part thereof
              is paid. Interest shall be calculated as set forth in the Note.

3.     Bank's Conclusive Determinations and Schedule. The Bank's determination
       with respect to any matter hereunder shall be conclusive, final and
       binding on Borrower, absent manifest

                                       2
<PAGE>   8

       error. The Bank shall from time to time record the date and amount of
       each Loan, the Applicable Rate, each date on which any part of principal,
       interest or any other amount shall be due and payable, and the amount and
       date of each payment of principal, interest or any other amount, on a
       schedule, which in the Bank's discretion may be computer-generated, and
       which is incorporated in, and is a part of, the Note and this Rider (the
       "Schedule"). The Schedule shall be conclusive, final and binding upon
       Borrower, absent manifest error; provided, however, that the failure of
       the Bank to record any of the foregoing shall not limit or otherwise
       affect the obligation of Borrower to pay all amounts owed to the Bank
       under the Note. Without limiting the foregoing, Borrower acknowledges
       that the Interest Period and the Applicable Rate with respect to any
       Outstanding Principal Amount are subject to the Bank's consent ordinarily
       negotiated between Borrower and the Bank by telephone, and Borrower
       agrees that in the event of any dispute as to any of the terms of any
       Loan, the determination of the Bank and its respective entry with respect
       thereto on its books and records and/or on the Schedule shall be
       conclusive, final and binding on Borrower, absent manifest error.

4.     Definitions. Each capitalized term not defined herein shall have the
       meaning ascribed thereto in the Note. The following definitions apply in
       this Rider and in the Note, and shall prevail over any different
       definitions in the Note.

       (a)    Alternate Rate: an annual Variable Prime-Based Rate equal to the
              Prime Rate plus the Margin.

       (b)    Applicable Rate: whichever of the Loan Rate or Increased Rate is
              the applicable interest rate at any time with respect to any
              Outstanding Principal Amount.

       (c)    Determination Time: 12:00 noon (or any later time determined by
              the Bank in its sole discretion), New York City time, of a Working
              Day that is three Working Days prior to the date of the Loan.

       (d)    Due Date: the date set forth in paragraph 1(b) of the Note or, if
              the Bank has extended such date pursuant to paragraph G(5) of the
              Note or by an agreement with Borrower, such extended date.

       (e)    Interest Period: any term of 1 day, 1 week, 1 to 6, 9 or 12
              months, or such other term as may be acceptable to the Bank in its
              discretion, as set forth above under Specific Terms or, if not so
              set forth, as selected or agreed to by the Bank in its discretion.
              A term shall not be considered as "Interest Period" during any
              period that the Applicable Rate is a Variable Prime-Based Rate.
              Each Interest Period shall commence immediately at the end of the
              preceding Interest Period, if any; if there had been no
              immediately preceding Interest Period with respect to any
              Outstanding Principal Amount, the Interest Period shall commence
              on the first Business Day on which (i) such amount shall be
              outstanding and (ii) the Applicable Rate is not a Variable
              Prime-Based Rate. If any Interest Period would otherwise come to
              an end on a day which is not a Working Day, its termination shall
              be postponed to the next day that is a Working Day unless it would
              thereby terminate in the next calendar month. In such

                                       3

<PAGE>   9

              case, such Interest Period shall terminate on the immediately
              preceding Working Day.

       (f)    LIBOR: the rate or rates established by the New York Branch of the
              Bank two Working Days prior to the date of the Loan, by applying
              the following: (i) the British Bankers Association ("BBA")
              Interest Settlement Rates for U.S. Dollars, as defined in the BBA
              official definitions and reflected on the Telerate BBA pages, for
              the applicable amounts and interest periods, which rates reflect
              the offered rates at which deposits are being quoted to prime
              banks in the London Interbank Market at 11:00 A.M. London Time
              calculated as set forth in said BBA official definition; or (ii)
              such other recognized source of London Eurodollar deposit rates as
              the Bank may determine from time-to-time. In the event the
              applicable BBA page or pages shall be replaced by another Telerate
              page or other Telerate pages for quoting London Eurocurrency
              rates, then rates quoted on said replacement page or pages shall
              be applied. If the Bank determines that London Eurocurrency rates
              are no longer being quoted (temporarily or permanently) on any
              Telerate pages or that Telerate is no longer functioning
              (temporarily or permanently) in substantially the same manner as
              on the date hereof, then the Bank shall notify the Borrower of a
              substitute, publicly available reference for the determination of
              LIBOR. If the Bank determines in its sole discretion that LIBOR
              cannot be determined or does not represent its effective cost of
              maintaining Loans under this Note, then interest shall accrue at
              the effective cost to the Bank to maintain the Loans (as
              determined by the Bank in its sole discretion).

       (g)    LIBOR-Based Rate: an annual rate equal to LIBOR plus the Margin,
              as determined by the Bank.

       (h)    Loan: (i) any loan advanced by the Bank to the Borrower under the
              Note; (ii) any rollover by the Bank of any such loan that is
              otherwise due and payable or (iii) any conversion of the
              Applicable Rate for any Outstanding Principal Amount from a rate
              that is a Variable Prime-Based Rate to one that is not, or vice
              versa.

       (i)    Loan Rate: the interest rate determined under subparagraph 1(a)
              and/or 2(b).

       (j)    Margin: as set forth under Specific Terms or, if not so set forth,
              2% per year.

       (k)    Note: the note of which this Rider is a part (including any and
              all riders and amendments to the Note).

       (l)    Outstanding Principal Amount: the outstanding principal amount of
              each Loan.

       (m)    Payment Date: the last Business Day of the applicable Interest
              Period or, if the applicable Loan Rate is a Variable Prime-Based
              Rate, the Due Date.

       (n)    Working Day: a Business Day on which banks are regularly open for
              business in London.

                                       4