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                                                           EXHIBIT 4.(a)(xxviii)


                               FACTORING AGREEMENT

         THIS FACTORING AGREEMENT made as of the 21 day of May, 2002 by and
between PLATINUM FUNDING CORP., as servicing agent, a New Jersey corporation,
having an office at Two University Plaza, Hackensack, New Jersey 07601
("Platinum") and MADGE NETWORKS, INC., a California Corporation, having a place
of business at One State Street Plaza, 12th Floor, New York, New York 10004
("Seller").

                              W I T N E S S E T H:
                              --------------------

         WHEREAS, Seller has requested that Platinum purchase from Seller, from
time to time, all of Seller's right, title and interest in and to certain
accounts receivable due to Seller from its customers; and

         WHEREAS, Platinum has agreed to purchase certain of such accounts
receivable from Seller, from time to time, upon the terms and subject to the
conditions set forth in this Agreement.

         NOW, THEREFORE, in order to induce Platinum to purchase such accounts
receivable, and for Ten ($10.00) Dollars and other good and valuable
consideration, the receipt and sufficiency of which being hereby acknowledged,
the parties hereto agree as follows:

         1.  Sale and Purchase of Accounts Receivable. Seller will tender to
Platinum certain of Seller's invoices to be rendered to Seller's customers
("Account Debtors") with respect to goods sold and delivered to, or services
performed for, such Account Debtors by Seller (individually, an "Account
Receivable" and collectively, the "Accounts Receivable"). Such invoices shall be
delivered by Platinum to the respective Account Debtors, in accordance with the
standard billing procedures of Platinum, together with or after notice from
Seller and/or Platinum to such Account Debtors of the irrevocable assignment to
Platinum of payment thereunder. Platinum will conduct such examination and
verification of the invoices so tendered, and such credit investigation of such
Account Debtors, as Platinum considers necessary or desirable, and will notify
Seller as to which of the individual Accounts Receivable so tendered, if any,
Platinum elects to purchase. Platinum shall at all times have the absolute right
in its sole discretion to reject any or all of the Accounts Receivable, whether
or not Platinum has previously purchased Accounts Receivable from Seller or
previously purchased Accounts Receivable of any particular Account Debtor.

         2.  Account Agreements. Those Accounts Receivable which Platinum elects
to purchase from Seller shall be purchased upon the terms and subject to the
conditions of separate Purchase and Sale Agreements, between Seller and
Platinum, the form of which has heretofore been provided to Seller (the "Account
Agreements"). Platinum shall advance against the Purchase Price (as defined in
the Account Agreements) for the Accounts Receivable Platinum elects to purchase
pursuant to the provisions hereof, seventy (70%) percent of the face amount of
such Accounts Receivable purchased. Platinum shall pay the balance of the
Purchase Price, as calculated pursuant to the applicable Account Agreement,
pursuant to the further provisions of this Section 2. For the purposes hereof,
the term "Schedule Closure Date" shall mean, with respect to each of

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the schedules or batches of Accounts Receivable purchased pursuant to each
Account Agreement (a "Schedule"), the date with respect to each Schedule on
which the applicable Account Debtors have either paid all such Accounts
Receivable in the Schedule or, a Chargeback (as defined in the Account
Agreements) has been taken thereagainst; provided, however, that Seller may, at
its election, repurchase any such Accounts Receivable from Platinum, for a price
equal to the face amount of such Account Receivable, in which event such Account
Receivable shall be deemed duly paid for the purposes of determining the
Schedule Closure Date. Notwithstanding anything to the contrary herein
contained, the Accounts Receivable purchased by Platinum may be aggregated and
administered as a single Account Receivable, or as several discreet Accounts
Receivable, in the discretion of Platinum (each, an "Aggregate Receivable" or
Schedule as previously defined). Periodically, from and after each Schedule
Closure Date, the balance of the Purchase Price, if any, payable in respect of
the Accounts Receivable purchased pursuant to each Account Agreement (the
"Purchase Price Balance") shall be aggregated with the Purchase Price Balance,
if any, from all other Schedules in respect of which there has occurred other
Schedule closures (the "Aggregate Purchase Price Balance"), and Platinum shall
credit to Seller's reserve account, the positive amount, if any, of such
Aggregate Purchase Price Balance. Chargebacks from all Account Agreements shall
be debited against the Seller's reserve account and the net credit balance shall
be rebated to the Seller in accordance with Platinum's standard rebate
practices. Capitalized terms not herein defined shall have the respective
meanings attributed thereto in the Account Agreement. In the event of any
conflict between the provisions of an Account Agreement and this Factoring
Agreement, the provisions of this Factoring Agreement shall govern and control.
Notwithstanding the first sentence of this Section 2, if either Seller or
Platinum shall fail to execute an Account Agreement with respect to a particular
Account Receivable tendered by Seller to Platinum, and Platinum shall
nevertheless pay an Advance Amount to Seller for such Account Receivable,
Platinum shall be presumed conclusively to have purchased, and Seller shall be
presumed conclusively to have sold, such Account Receivable pursuant to an
Account Agreement, and such Account Receivable shall be governed by the terms
and conditions (including, without limitation, Seller's representations,
warranties and covenants to Platinum contained therein) set forth in the Account
Agreement in the form heretofore provided to Seller.

         3.  Conditions Precedent. Platinum shall not purchase any Accounts
Receivable pursuant to an Account Agreement unless and until each of the
following conditions shall have been satisfied:

             (a)  Platinum and Seller shall have entered into a Security
Agreement in the form heretofore provided to Seller (the "Security Agreement"),
to secure Seller's performance of the representations, warranties and covenants
set forth in the Account Agreements on Seller's part to be performed (the
"Representations") (but not the payment of the Accounts Receivable purchased
thereby);

             (b)  Madge Networks N.V. shall have executed and delivered to
Platinum a Performance Guaranty in the form heretofore provided to Seller (the
"Performance Guaranty"), with respect to Seller's performance of the
Representations on Seller's part to be performed (but not the payment of the
Accounts Receivable purchased thereby);


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             (c)  Seller shall have authorized Platinum to file Uniform
Commercial Code financing statements for filing with the appropriate filing
officer or officers in each jurisdiction where, in the reasonable opinion of
Platinum, such filing is necessary or desirable to perfect the security
interests granted pursuant to the Security Agreement and to provide notice of
the factoring arrangement; and

             (d)  Seller shall have executed and delivered to Platinum an
Account Agreement in the form heretofore provided to Seller, together with the
schedule of proposed Accounts Receivable attached thereto as Schedule A, which
Schedule A shall be duly executed and dated by Seller.

         4.  Cross-Collateralization. If a Default (as defined in the Security
Agreement) shall have occurred, Platinum shall have the right, which may be
exercised in its sole and absolute discretion at any time and from time to time
during the continuance of such Default, to apply all amounts collected with
respect to Accounts Receivable, as follows, before any payment from such
collections shall be made to Seller: (i) first, against the unreimbursed balance
of the Advance Amounts made by Platinum to Seller with respect to Accounts
Receivable purchased from Seller under one or more Account Agreements; (ii)
next, to the payment of all fees and expense reimbursements (as described in the
Account Agreements) accrued with respect to Accounts Receivable purchased by
Platinum from Seller, whether or not such fees have become due and payable
pursuant to the terms of the Account Agreements; and (iii) the balance, if any,
to the payment of any and all other liabilities and obligations of Seller to
Platinum pursuant to this Factoring Agreement, the Security Agreement, the
Account Agreements and any other agreement entered into between Platinum and
Seller concurrently or in connection herewith.

         5.  Collection of Accounts Receivable. Seller will instruct all of the
Account Debtors obligated with respect to Accounts Receivable purchased by
Platinum to mail or deliver payments on such Account Receivable directly to
Platinum at its address herein above set forth or at such other address as
Platinum may specify in a written notice to Seller. Such instructions shall not
be rescinded or modified without Platinum's prior written consent. If, despite
such instructions, Seller shall receive any collections or other proceeds of the
Accounts Receivable purchased by Platinum, Seller shall immediately deliver such
payments, in the exact form received, to Platinum. Failure to deliver such
payments to Platinum as provided herein shall be deemed a default under the
Factoring Agreement. All payments received by Platinum shall be applied as
provided in Sections 4 and 5 above. Platinum shall have no liability to Seller
for any mistake in the application of any payment received with respect to any
Account Receivable, provided Platinum shall have acted in good faith and without
gross negligence in respect thereof.

         6.  Payment of Expenses and Taxes. Seller will (a) pay or reimburse
Platinum for all of Platinum's out-of-pocket costs and expenses incurred in
connection with the preparation and execution of, and any amendment, supplement
or modification to, this Factoring Agreement, the Security Agreement, any of the
Account Agreements and any other documents prepared in connection herewith or
therewith, and the consummation of the transactions contemplated hereby and
thereby, including, without limitation, the fees and disbursements of counsel to
Platinum; (b) pay or reimburse Platinum for all its costs


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and expenses incurred in connection with the enforcement or preservation of any
rights under this Factoring Agreement, the Security Agreement, the Account
Agreements and such other documents, and the verification of the Accounts
Receivable and the creditworthiness of the Account Debtors, including, without
limitation, fees and disbursements of counsel to Platinum; (c) pay, indemnify,
and hold harmless from and against any and all recording and filing fees and any
and all liabilities with respect to, or resulting from, any delay in paying,
stamp, excise and other taxes, if any, which may be payable or determined to be
payable in connection with the execution and delivery of, or consummation of,
any of the transactions contemplated by, or any amendment, supplement or
modification of, or any waiver or consent under or in respect of, this Factoring
Agreement, the Security Agreement, the Account Agreements and any such other
documents; and (d) pay, indemnify, and hold Platinum harmless from and against
any and all other liabilities, obligations, losses, damages, penalties, actions,
judgments, suits, costs, expenses or disbursements of any kind or nature
whatsoever with respect to the execution, delivery, enforcement and performance
of this Factoring Agreement, the Security Agreement, the Account Agreements and
such other documents (all of the foregoing being hereinafter collectively
referred to as the "indemnified liabilities"); provided, however, that Seller
shall have no obligation hereunder to Platinum with respect to indemnified
liabilities arising from (i) the gross negligence or willful misconduct of
Platinum, (ii) salaries and other amounts payable by Platinum to its employees
in the ordinary course of business or (iii) expenses incurred by Platinum (other
than those specifically enumerated in clauses (a), (b) and (c) above) in the
ordinary course of business in connection with the performance of its
obligations hereunder. In recognition of Platinum's right to have its attorneys'
fees and other expenses incurred in connection with this Factoring Agreement
secured by the collateral pledged by Seller pursuant to the Security Agreement,
notwithstanding payment in full of all obligations by Seller, Platinum shall not
be required to record any terminations or satisfactions of any of Platinum's
liens on the collateral unless and until Seller has executed and delivered to
Platinum, a general release in a form reasonably satisfactory to Platinum.
Seller understands that this provision constitutes a waiver of its rights under
section 9-513 of the Uniform Commercial Code. The agreements in this Section 6
shall survive the termination of this Factoring Agreement.

         7.  Amendments. Any provisions hereof may be modified or amended only
by a written instrument expressly referred hereto duly executed on behalf of
Platinum and Seller by their respective duly authorized representatives.

         8.  Termination. This Factoring Agreement shall begin on the date
hereof and, unless sooner terminated as herein provided, terminate at 11:59 p.m.
on the day immediately preceding the second year anniversary of the date hereof
(the "Scheduled Term"), except that the Representations, and the remedies of
Platinum for a breach of such Representations, shall survive the termination of
this Factoring Agreement. Such termination shall not affect the rights of
Platinum in enforcing its remedies against Seller or any collateral upon any
default by Seller hereunder or upon a Default under the Security Agreement. This
Factoring Agreement shall be deemed renewed from year to year (the "Rescheduled
Term") unless Seller shall deliver written notice of cancellation to Platinum at
least 60 days but not more than 90 days prior to the expiration date then in
effect hereunder.


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         9.  Fee. The fee to be earned by Platinum for the purchase of Accounts
Receivable from Seller, as set forth in the Fee and Reimbursements Schedule
attached to the Account Agreements (the "Fee"), has been established after
negotiation between the parties based upon the delivery by Seller of not less
than $300,000.00 per month of approved Accounts Receivable (the "Monthly Base
Sales Amount") to Platinum during each 30 day period (a "Term Month") of the
Scheduled Term or Rescheduled Term, as applicable. Seller expressly acknowledges
that Platinum has agreed thereto in reliance upon Seller's agreement during each
Term Month to deliver at least the Monthly Base Sales Amount and that Platinum
requires an increased Fee in the event a lesser volume of approved Accounts
Receivable is agreed upon in any Term Month. Consequently, if the aggregate
amount of approved Accounts Receivable delivered by Seller to Platinum during
any Term Month, whether by reason of Seller's premature termination, reduced
level of sales, or otherwise, shall be less than the Monthly Base Sales Amount,
then Seller shall pay to Platinum an adjustment fee on account of such Term
Month equal to (a) the product of (i) the actual aggregate fees earned by
Platinum from the purchase of Accounts Receivable from Seller for the applicable
Term Month (or then expired portion thereof) (the "Partial Fee") and (ii) a
fraction, the numerator of which is the Monthly Base Sales Amount and the
denominator of which is the actual aggregate amount of Accounts Receivable
theretofore delivered by Seller in such Term Month, less (b) the Partial Fee,
provided, however if, in any Term Month, Seller shall deliver no Accounts
Receivable to Platinum, then Seller shall pay to Platinum in respect of such
Term Month an adjustment fee equal to the product of (c) the Monthly Base Sales
Amount and (d) a fraction, the numerator of which is the aggregate Fees
theretofore earned by Platinum pursuant to this Factoring Agreement and the
denominator of which is the actual aggregate amount of Accounts Receivable
theretofore purchased by Platinum pursuant to this Factoring Agreement (the "No
Delivery Fee"). Notwithstanding anything to the contrary herein contained, this
Factoring Agreement may be terminated by Platinum, in Platinum's sole discretion
on three (3) days written notice to Seller if, for a period of forty five (45)
days, Seller shall deliver no Accounts Receivable to Platinum for purchase as
herein provided (a "No Delivery Termination"). Upon any such No Delivery
Termination, Seller shall pay to Platinum the No Delivery Fee calculated as
above-provided, for each and every unexpired Term Month remaining in the
Scheduled Term or Rescheduled Term, as applicable.

         10. Notices. All notices and other communications hereunder shall be
deemed to have been sufficiently given when mailed, postage prepaid, by
certified or registered mail, sent by courier or telefaxed, return receipt
requested, or confirmation of receipt requested in the case of a telefax, and
the sender shall have received such return receipt or confirmation, addressed to
the party intended to receive the same at the address herein above set forth.
Each of the parties hereto shall have the right to rely on as an original any
notice given hereunder by telefax as aforesaid.

         11. Successors, Governing Law, Consent to Jurisdiction, Waiver of
Service. This Factoring Agreement shall inure to the benefit of and be binding
upon the successors and assigns of the parties hereto, except that this
Factoring Agreement may not be assigned by Seller without the prior written
consent of Platinum. This Factoring Agreement shall be governed by and construed
in accordance with the laws of the State of New Jersey applicable to agreements
made and to be performed exclusively within such state. The


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parties hereto mutually agree that any legal action relating to or arising from
the Factoring Agreement, the Security Agreement, the Account Agreements or the
Performance Guaranty (or Guaranties), if any, or relating in any way to the
factoring relationship between Platinum and the Seller and Guarantor(s), shall
be maintained only in (a) the Superior Court of the State of New Jersey, County
of Bergen, (b) the federal courts in and for the District of New Jersey, Newark
vicinage, (c) the Supreme Court of the State of New York, County of New York, or
(d) the federal courts in and for the Southern District of New York (the "Courts
of Jurisdiction"), and the parties hereto expressly consent and agree, and waive
any objection, to the jurisdiction of the Courts of Jurisdiction over any such
legal action, and over the parties hereto, and to the laying of venue in any of
the Courts of Jurisdiction. The parties expressly agree that no legal action may
be maintained between or among the parties hereto other than in the Courts of
Jurisdiction, however, nothing in this paragraph shall be construed to limit the
rights of the parties to domesticate, or otherwise pursue, any judgment obtained
in the Courts of Jurisdiction in any other court, state, territory or nation.
Furthermore, the parties hereto expressly agree to waive all otherwise
applicable statutes, rules, or other requirements relating to the service of
legal process, including, but not limited to, the service of a summons and/or
complaint, and hereby agree to accept service of process in any such legal
action pursuant solely to the notice provisions contained herein. Any such
service of legal process made pursuant to the notice provisions hereof shall be
deemed to be good and valid service, without regard for any contrary or
inconsistent statute, rule or provision.

         12. Bankruptcy. The parties expressly agree that in the event Seller
voluntarily files for protection pursuant to any provision of the United States
Bankruptcy Code or, in the event an involuntary petition in bankruptcy is filed
against the Seller, (a) this Factoring Agreement shall automatically terminate
upon such filing, and (b) Seller's obligations under this Factoring Agreement,
the Security Agreement, the Account Agreements and the Performance Guaranties,
if any, shall be automatically accelerated and all sums due under any provision
of the aforementioned documents shall be immediately due and payable. Following
either of the aforementioned bankruptcy filings, Platinum may elect to offer
financing to the debtor-in-possession, but nothing in this paragraph shall
obligate Platinum to offer or provide such financing.

         13. Merger. It is understood and agreed that all understandings and
agreements heretofore had between the parties, if any, with respect to the
subject matter hereof are merged into this Factoring Agreement which alone fully
and completely expresses their agreement.

         14. Audit. Platinum shall be entitled in its sole discretion, upon at
least two (2) business days notice to Seller, to conduct or cause to be
conducted an audit of Seller's books and records and Seller hereby agrees to
make available all invoices, bills, bank books and account statements, cancelled
checks, accounts receivable and payable ledgers, tax returns and like financial
information, and otherwise fully to cooperate with Platinum or its designated
representative, in connection therewith. Seller shall pay upon demand as set
forth in the Account Agreement(s) the cost of not more than two (2) of such
audits performed in any twelve (12) month period; provided, however, that if
there shall occur a


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Default and this Agreement shall not be terminated by Platinum, Seller shall
thereafter pay the cost of any and all such audits conducted or caused to be
conducted by Platinum.

         15. Jury Trial Waiver. The Parties hereto do hereby waive any and all
right to a trial by jury in any action or proceeding arising out of this
Factoring Agreement.

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


                                        PLATINUM FUNDING CORP.,
                                        as servicing agent.


                                        By: /s/ M D WEINBURG
                                            ------------------------------------
                                            Name:  Mark D. Weinberg
                                            Title: President


                                        MADGE NETWORKS, INC.


                                        By: /s/ M MALINA
                                            ------------------------------------
                                            Name:  Martin Malina
                                            Title: President






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