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                                                                    EXHIBIT 10.8


[SIEMENS LOGO]


                              EMPLOYMENT AGREEMENT


         EMPLOYMENT AGREEMENT effective as of April 1, 1999, by and between
Unisphere Solutions, Inc. a Delaware corporation with its principal place of
business at 200 Wheeler Road, Burlington, Massachusetts 01803 (the "Company"),
and Martin Clague, residing at Five Ononaga Street Rye, New York 10580 (the
"Executive").

         WHEREAS, the Company wishes to offer employment to the Executive and
the Executive wishes to accept such offer, on the terms set forth below.

         Accordingly, the parties hereto agree as follows:

1. TERM. The Company hereby employs the Executive, and the Executive hereby
accepts such employment, for an initial term commencing as of April 1, 1999 and
ending on September 30, 2002, unless sooner terminated in accordance with the
provisions of Section 4 or Section 5; with such employment to continue for
successive one-year periods in accordance with the terms of this Agreement
(subject to termination as aforesaid) unless either party notifies the other
party in writing prior to 60 days before the expiration of the initial term and
each annual renewal thereof (the period during which the Executive is employed
hereunder being hereinafter referred to as the "Term"). Notwithstanding anything
to the contrary contained in this Agreement, in no event shall the Term
commence, or any provision
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of this Agreement be effective unless and until the Executive executes a
Non-Competition and Non-Solicitation Agreement and an Employee Patent and
Secrecy Agreement in the forms attached hereto as Exhibits A and B,
respectively.

2. DUTIES. During the Term, the Executive shall be employed by the Company as
President and Chief Executive Officer of the Company, reporting to and serving
at the pleasure of the Board of Directors of the Company, and as such, the
Executive shall faithfully perform for the Company the duties of said office and
shall perform such other duties of an executive, managerial or administrative
nature as shall be specified and designated from time to time by the Board of
Directors of the Company. The Executive shall devote all of his business time
and effort to the performance of his duties hereunder.

3. COMPENSATION.

         3.1 BASE SALARY. For the period of April 1, 1999 through September 30,
1999, the Company shall pay the Executive a salary at the rate of $70,000 per
month, and for the period from October 1, 1999 through September 30, 2000, the
Company shall pay the Executive a base salary at the rate of $36,666 per month.
For the period from October 1, 2000 to the end of the Term of this Agreement,
the Company shall pay the Executive a base salary which will be determined by
the Board of Directors of the Company, but in no event shall this base salary be
less

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than $36,666 per month. The Executive shall receive payment of his base salary
from the Company in accordance with the customary payroll practices of the
Company applicable to senior executives.

         3.2 ANNUAL BONUS. In addition to the Executive's base salary, as set
forth in Section 3.1 of this Agreement, for each fiscal year of the Company
beginning on or after October 1, 1999 and ending during the Term, the Executive
shall have the opportunity to earn an annual bonus. The annual bonus target for
the Executive for the period of October 1, 1999 through September 30, 2000 shall
be set at 100% of the Executive's base salary actually paid during such period
provided that there is 100% achievement of the annual bonus plan's financial and
business goals as determined by the Board of Directors of the Company. The
annual bonus target for the Executive for the period of October 1, 2000 through
September 30, 2001 and for the period of October 1, 2001 through September 30,
2002 and for any periods thereafter during the Term of this Agreement shall be
50% of the Executive's base salary actually paid during such periods if there is
100% achievement of the annual bonus plan's financial and business goals as
determined by the Board of Directors of the Company. If, in any of the periods
set forth in the immediately preceding sentence, the Executive is not eligible
for an award from the Company under any long term

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incentive compensation programs (which term includes but is not limited to any
stock appreciation right or stock option plans), the Executive's annual bonus
target for the period during which he is not eligible for such long term
incentive compensation program award shall be 100% of the Executive's base
salary actually paid during that period if there is 100% achievement of the
annual bonus plan's financial and business goals as determined by the Board of
Directors of the Company. If the performance of the Company either exceeds or
does not achieve 100% of the annual bonus plan's financial and business goals
during a particular period, the amount of the annual bonus to be paid to the
Executive by the Company pursuant to this Section 3.2 during that period shall
be adjusted upward or downward according to guidelines established for such
annual bonus plan by the Board of Directors of the Company.

         3.3 LONG TERM INCENTIVE COMPENSATION PROGRAM. The Executive shall be
eligible to participate in any long term incentive compensation program which
the Board of Directors may establish for senior executives of the Company.

         3.4 BENEFITS - IN GENERAL. Except with respect to benefits of a type
otherwise provided for under Section 3.5, the Executive shall be permitted
during the Term to participate in any group insurance, retirement plans, fringe
benefit programs and similar benefits that may be available to other senior


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executives of the Company generally, on the same terms as such other executives,
in each case to the extent that the Executive is eligible under the terms of
such plans or programs.

         3.5 SPECIFIC BENEFITS. Without limiting the generality of Section 3.4,
during the Term the Company shall pay to the Executive a car allowance of $1500
per month. The amount of this car allowance will not be considered compensation
for any purpose under the benefits set forth in Section 3.4 nor included in the
levels established in Sections 3.1 and 3.2 above.

         The Executive shall be eligible for five weeks of paid vacation
annually.

         In accordance with the standard policy of the Company, the Company
shall reimburse the Executive for reasonable temporary living expenses for the
period from April 1, 1999 until the earlier of September 30, 1999 or the date
the Executive purchases a new residence in the Boston, Massachusetts area. The
Company will also reimburse the Executive for any of his closing costs and fees
incurred in acquiring a residence in the Boston, Massachusetts area, in
accordance with the standard relocation policy of the Company. Further, the
Company will provide the Executive with full applicable relocation services if
Executive sells his home in Rye, New York and purchases a new primary family
residence within 50 miles of the Company's headquarters on or before September
30, 2001, in accordance with the

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Company's standard policy; provided, however, any amount that the Company has
reimbursed the Executive for his closing costs and fees for acquiring an interim
residence in the Boston, Massachusetts area shall be deducted from the amount
the Executive will receive under the Company's policy for relocation of his
primary residence to within 50 miles of the Company's headquarters.

         3.6 EXPENSES. The Company shall pay or reimburse the Executive for all
ordinary and reasonable out-of-pocket expenses actually incurred (and, in the
case of reimbursement, paid) by the Executive during the Term in the performance
of the Executive's services under this Agreement in accordance with the policies
of the Company with respect to reimbursement for such expenses.

4. TERMINATION UPON DEATH OR DISABILITY. If the Executive dies during the Term,
the Term shall terminate as of the date of death, and the obligations of the
Company to or with respect to the Executive shall terminate in their entirety
upon such date except as otherwise provided under this Section 4. If the
Executive becomes disabled for purposes of the long-term disability plan of the
Company for which the Executive is eligible, the Company shall have the right,
to the extent permitted by law, to terminate the employment of the Executive
upon notice in writing to the Executive. Upon termination of

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employment due to death or disability, (i) the Executive (or the Executive's
estate or beneficiaries in the case of the death of the Executive) shall be
entitled to receive his base salary as set forth in Section 3.1 and other
benefits, including any annual bonus, earned and accrued under' this Agreement
prior to the date of termination (and reimbursement under this Agreement for
expenses incurred prior to the date of termination) , and (ii) the Executive
(or, in the case of his death, his estate and beneficiaries) shall have no
further rights to any other compensation or benefits hereunder on or after the
termination of employment, or any other rights hereunder.

5.       CERTAIN TERMINATIONS OF EMPLOYMENT.

         5.1 TERMINATION OF EMPLOYMENT BY THE COMPANY OR BY THE EXECUTIVE ON OR
BEFORE SEPTEMBER 30, 1999. If the Company terminates the employment of the
Executive with the Company on or before September 30, 1999 for any reason or if
the Executive terminates his employment with the Company on or before September
30, 1999 for any reason, the Company shall pay the Executive an amount of
$210,000, less applicable withholding taxes and FICA, provided, however, that
the Company's obligation to make this payment to the Executive is conditioned
upon the Executive's execution of a General Release in the standard form used by
the Company and is in lieu of any other payments that may otherwise be due to
the Executive under this Agreement or

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under any severance or separation plan, program or policy of the Company.

         5.2      TERMINATION BY THE COMPANY FOR CAUSE.

                  (a) For purposes of this Agreement, "Cause" shall mean the
Executive's:

                           (i) commission of a felony reflecting adversely on
the Company, a crime of moral turpitude, dishonesty, breach of trust or
unethical business conduct, or any crime involving the Company;

                           (ii) engagement in the performance of his duties
hereunder, or otherwise to the detriment of the Company, in willful misconduct,
willful or gross neglect, fraud, misappropriation or embezzlement;

                           (iii) failure to adhere to the reasonable directions
of the Board of Directors, to adhere to the Company's policies and practices or
to devote all of his business time and efforts to the Company;

                           (iv) breach of either of the agreements attached
hereto as Exhibits A and B; or

                           (v) breach in any material respect of the terms and
provisions of this Agreement;



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provided that the Company shall not be permitted to terminate the Executive for
Cause except on written notice given to the Executive.

                  (b) With respect to Section 5.2(a)(iii) above, Cause shall not
be deemed to exist unless written notice of such termination on account of Cause
is given by the Company to the Executive, in accordance with Section 5.2(c)
below, and the Executive is given one opportunity in the 30 days from the date
notice of such termination to cure such event or condition, and, if the
Executive does so, such event or condition shall not constitute Cause hereunder.

                  (c) Subject to Section 5.2(b) above, the Company may terminate
the Executive's employment hereunder for Cause on at least 30 days' written
notice given to the Executive. If the Company terminates the Executive for
Cause, and such termination is not covered by Section 5.1(i) the Executive shall
receive his base salary as set forth in Section 3.1 in effect at the time of his
termination of employment from the Company and other benefits (but, in all
events, and without increasing the Executive's rights under any other provision
hereof, excluding any annual bonus not yet paid) earned and accrued under this
Agreement prior to the termination of employment (and reimbursement under this
Agreement for expenses incurred prior to the termination of employment); and
(ii) the Executive shall

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have no further rights to any other compensation or benefits hereunder on or
after the termination of employment except as set forth under the terms of
applicable compensation or benefit plans or programs, or any other rights
hereunder.

         5.3      TERMINATION BY THE COMPANY WITHOUT CAUSE.

                  The Company may terminate the Executive's employment at any
time for any reason or no reason. If the Company terminates the Executive's
employment and the termination is not covered by Sections 4, 5.1, or 5.2 (i) the
Executive shall receive his base salary as set forth in Section 3.1 and other
benefits, including any annual bonus earned and accrued under this Agreement or
applicable compensation plan, to the extent such base salary and bonus and
benefits are earned and accrued under this Agreement prior to the termination of
employment (and reimbursement under this Agreement for expenses incurred prior
to the termination of employment); (ii) the Executive shall receive (A) a cash
payment equal to his monthly base salary at the time of his termination of
employment from the Company for 12 months following such termination of
employment and (B) for a period of 12 months after such termination of
employment such continuing coverage under the Company's group health plans as
the Executive was receiving at the time of such termination of employment; and
(iii) the Executive shall have no further rights to any other compensation or
benefits hereunder on or after the

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termination of employment except as set forth under the terms of applicable
compensation or benefit plans or programs, or any other rights hereunder;
provided that the Company's obligations with respect to the payments and
benefits provided for in this Section 5.3 are conditioned upon the Executive's
execution of a General Release in the standard form used by the Company. It is
expressly understood and agreed that any payment made pursuant to this Section
5.3 shall be in lieu of any other payments that may otherwise be due to the
Executive under this Agreement or under any severance or separation plan,
program or policy of the Company.

         5.4      TERMINATION BY THE EMPLOYEE.

                  (a) For purposes of this Agreement, "Good Reason" shall mean
only:

                           (i) the Company requiring the Executive to be based
at any location that is more than 50 miles from the city limits of Boston,
Massachusetts;

                           (ii) the Company reducing the Executive's base salary
as set forth in Section 3.1 of this Agreement;

                           (iii) the Company reducing the Executive's annual
bonus target as set forth in Section 3.2 of this Agreement;


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                           (iv) the Company, materially reducing the Executive's
responsibilities and authority regarding the operations of the Company; or

                           (v) the Executive not accepting employment with a
person or entity which is not affiliated with Siemens AG, after such person or
entity either acquires ownership of 51% or more of the outstanding voting
securities of the Company or acquires substantially all of the assets of the
Company.

                  Notwithstanding the foregoing, Good Reason shall not be deemed
to exist unless written notice of such termination on account of Good Reason is
given by the Executive to the Company, in accordance with Section 6.5, no later
than 30 days after the event giving rise to the notice occurs, and the Company
is given 30 days from the date notice of such termination is given to cure such
event or condition, and, if the Company does so, such event or condition shall
not constitute "Good Reason" hereunder.

                  (b) If the Executive voluntarily terminates his employment
with the Company for Good Reason, and the termination is not otherwise covered
by Sections 4, 5.1, or 5.4(c), (i) the Executive shall receive his base salary
under Section 3.1 and other benefits, including any annual bonus, earned and
accrued under this Agreement prior to the termination of employment (and
reimbursement under this Agreement for expenses incurred prior to the
termination of employment); (ii) the Executive shall

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receive (A) a cash payment equal to his monthly base salary at the. time of his
termination of employment from the Company for 12 months following such
termination of employment and (B) for a period of 12 months after such
termination of employment such continuing coverage under the Company's group
health plans as the Executive was receiving at the time of such termination of
employment; and (iii) the Executive shall have no further rights to any other
compensation or benefits hereunder; provided that the Company's obligations with
respect to the payments and benefits provided for in this Section 5.4 (b) are
conditioned upon the Executive's execution of a General Release in the standard
form used by the Company. It is expressly understood and agreed that any payment
made pursuant to this Section 5.4 (b) shall be in lieu of any other payments
that may otherwise be due to the Executive under this Agreement or under any
severance or separation plan, program or policy of the Company.


                  (c) The Executive may terminate his employment with the
Company on at least 30 days' and not more than 60 days, written notice to the
Company. If the Executive terminates his employment and such termination is not
covered by Section 4, 5.1 or 5.4(b), (i) the Executive shall receive his base
salary under Section 3.1 in effect at the time of his termination of employment
from the Company and other benefits (but, in all events, and without increasing
the Executive's rights under any

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other provision hereof, excluding any annual bonus not yet paid) earned and
accrued under this Agreement prior to his termination of employment (and
reimbursement under this Agreement for expenses incurred prior to termination of
employment); and (ii) the Executive shall have no further rights to any other
compensation or benefits hereunder on or after the termination of employment
except as set forth under the terms of applicable compensation or benefit plans
or programs, or any other rights hereunder.

         5.5 Notwithstanding clause (ii) (B) of the second sentence of Section
5.3 (a) and clause (ii) (B) of the first sentence of Section 5.4 (b), (i)
nothing herein shall restrict the ability of the Company to amend or terminate
the plans and programs referred to in such clauses from time to time in its sole
discretion, and (ii) the Company shall in no event be required to provide and
benefits otherwise required by such clauses (ii) (B) after such time as the
Executive becomes entitled to receive benefits of the same type from another
employer or recipient of the Executive's services (such entitlement being
determined without regard to any individual waivers or other similar
arrangements).

6.       OTHER PROVISIONS.

         6.1 SEVERABILITY. The Executive acknowledges and agrees that he has had
an opportunity to seek advice of counsel in

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connection with this Agreement. If it is determined that any of the provisions
of this Agreement, or any part thereof, is invalid or unenforceable, the
remainder of the provisions of this Agreement shall not thereby be affected and
shall be given full effect, without regard to the invalid portions.

         6.2 DURATION AND SCOPE OF COVENANTS. If any court or other
decision-maker of competent jurisdiction determines that any of Executive's
covenants contained in this Agreement, is unenforceable because of the duration
or geographical scope of such provision, then, after such determination has
become final and unappealable, the duration or scope of such provision, as the
case may be, shall be reduced so that such provision becomes enforceable and, in
its reduced form, such provision shall then be enforceable and shall be
enforced.

         6.3 DISPUTE RESOLUTION.

                  (a) Any and all claims, disputes, and controversies between
the Executive and the Company with respect to interpretation, construction,
breach, enforceability, and/or enforcement of the terms and provisions of this
Agreement (a "Dispute") shall be finally resolved as provided in this Section
6.3 by binding arbitration. Arbitration shall be the exclusive means for
determination of all matters as above provided, and neither party shall
otherwise institute any action or proceeding in any court of law or equity,
state or federal, other than

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respecting enforcement of the arbitrator's decision or award hereunder. The
foregoing shall be a bona fide defense in any action or proceeding where the
matter in dispute was to be arbitrated or is being arbitrated pursuant to this
Agreement.

                  (b) The Company (or its successor in interest) or the
Executive shall have the right to submit a Dispute to arbitration, by delivery
to the other, by certified mail, or a written notice and demand for arbitration
of such Dispute. Arbitration shall be by the American Arbitration Association
(the "AAA") in accordance with its Rules applicable to such Disputes (the
"Rules"), by a neutral and impartial arbitrator acceptable to the Company and
the Executive. If such an arbitrator has not been selected by the Company and
the Executive within sixty days after AAA first provides a list of eligible
arbitrators, or within thirty days after the occurrence of a vacancy, a neutral
and impartial arbitrator shall be selected and appointed by the American
Arbitration Association, in accordance with its Rules. Unless otherwise required
under applicable law, the arbitration proceedings shall be conducted in the city
where the principal place of business of the Company is situated at the date of
this Agreement or a city mutually agreed to by the parties, and the procedural
rules of the place of arbitration shall apply. Each party shall be entitled to
be represented by legal counsel.


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                  (c) The arbitration proceedings (including discovery and the
giving of testimony) shall be conducted in strictest confidence pursuant to a
confidentiality agreement signed by the parties and devised to protect the
confidentiality of and valuable rights of the Company in the Confidential
Company Information (as defined in the Employee Patent and Secrecy Agreement)
and trade secrets as well as the confidentiality of any other confidential
information included in such proceedings. The arbitrator shall have the power
and authority to make such decisions and awards as he or she deems appropriate,
consistent with applicable law. To the extent applicable law sets particular
requirements for the conduct of such arbitration proceedings, such as, any with
respect to discovery, cross-examination, testimony, or availability of rights
and remedies, the arbitration proceedings shall be conducted in compliance with
those requirements.

                  (d) Subject to applicable law, the arbitrator may grant
compensatory damages and costs to the prevailing party (but not punitive or
exemplary damages and attorneys, fees and costs related to punitive or exemplary
damages) and injunctions that he or she may deem necessary or advisable directed
to or against a party, including a direction or order requiring specific
performance of any covenant, agreement or provision of this Agreement as a
result of a breach or threatened breach.

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Any decision or awarded of the arbitrator shall be final, binding and conclusive
upon the parties and said decision and award may be entered as a final judgment
in any court of competent jurisdiction.

                  (e) Subject to the foregoing, the costs of such arbitration
shall be borne equally by the parties, except that each party shall bear its own
attorneys fees and costs.

         6.4 SET-OFF. The Executive acknowledges and agrees, without limiting
the rights of the Company otherwise available at law or in equity, that the
Company may set against any or all amounts payable to the Executive hereunder
any or all amounts payable by the Executive to the Company.

         6.5 NOTICES. Any notice or other communication required or permitted
hereunder shall be in writing and shall be delivered personally, telegraphed,
telexed, sent by facsimile transmission or sent by certified, registered or
express mail, postage prepaid. Any such notice shall be deemed given when so
delivered personally, telegraphed, telexed or sent by facsimile transmission or,
if mailed, five days' after the date of deposit in the United States mails as
follows:

                           (i)      If to the Company, to:

                                    Chairman of the Board of Directors
                                    Unisphere Solutions, Inc.
                                    200 Wheeler Road
                                    Burlington, Massachusetts 01803



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                           (ii)     If to the Executive, to:

                                    Mr. Martin Clague
                                    Currently at:
                                    Five Onondaga Street
                                    Rye, New York 10580


                  Any such person may by notice given in accordance with this
Section 6.5 to the other parties hereto designate another address or person for
receipt by such person of notices hereunder.

         6.6 ENTIRE AGREEMENT. Other than with respect to the Non-Competition
and Non-Solicitation Agreement and Patent and Secrecy Agreement between the
Company and the Executive attached hereto as Exhibits A and B, as they may be
amended from time to time, relating to, among other things, non-competition,
non-solicitation, confidentiality and intellectual property, which agreements
shall survive in their entirety without regard to this Agreement, this Agreement
contains the entire agreement between the parties with respect to the subject
matter hereof and supersedes all prior agreements, written or oral, with respect
thereto.

         6.7 WAIVERS AND AMENDMENTS. This Agreement may be amended, superseded,
canceled, renewed or extended, and the terms hereof may be waived, only by a
written instrument signed by the parties or, in the case of a waiver, by the
party waiving compliance. No delay on the part of any party in exercising any


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right, power or privilege hereunder shall operate as a waiver thereof, nor shall
any waiver on the part, of any party of any such right, power or privilege nor
any single or partial exercise of any such right, power or privilege, preclude
any other or further exercise thereof or the exercise of any other such right,
power or privilege.

         6.8 GOVERNING LAW. THIS AGREEMENT SHALL BE GOVERNED BY AND CONSTRUED IN
ACCORDANCE WITH THE LAWS OF THE COMMONWEALTH OF MASSACHUSETTS WITHOUT REGARD TO
PRINCIPLES OF CONFLICTS OF LAW.

         6.9 ASSIGNMENT. This Agreement, and the Executive's rights and
obligations hereunder, may not be assigned by the Executive; any purported
assignment by the Executive in violation hereof shall be null and void. In the
event of any sale, transfer or other disposition of all or substantially all of
the Company's assets or business, whether by merger, consolidation or otherwise,
the Company may assign this Agreement and its rights hereunder.

         6.10 WITHHOLDING. The Company shall be entitled to withhold from any
payments or deemed payments any amount of tax withholding it determines to be
required by law.

         6.11 BINDING EFFECT. This Agreement shall be binding upon and inure to
the benefit of the parties and their respective

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successors, permitted assigns, heirs, executors and legal representatives.

         6.12 COUNTERPARTS. This Agreement may be executed by the parties hereto
in separate counterparts, each of which when so executed and delivered shall be
an original but all such counterparts together shall constitute one and the same
instrument. Each counterpart may consist of two copies hereof each signed by one
of the parties hereto.

         6.13 SURVIVAL. Anything contained in this Agreement to the contrary
notwithstanding, the provisions of Sections 6.3, 6.4 and 6.10, and the other
provisions of this Section 6 (to the extent necessary to effectuate the survival
of Sections 6.3, 6.4 and 6.10), shall survive termination of this Agreement and
any termination of the Executive's employment hereunder.

         6.14 EXISTING AGREEMENTS. The Executive represents to the Company that
he is not subject or a party to any employment or consulting agreement,
non-competition covenant or other agreement, covenant or understanding which
might prohibit him from executing this Agreement or limit his ability to fulfill
his responsibilities hereunder.

         6.15 HEADINGS. The headings in this Agreement are for reference only
and shall not affect the interpretation of this Agreement.


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         6.16 PARACHUTES. If all, or any portion, of the Payments provided under
this Agreement, either alone or together with other payments and benefits which
the Executive receives or is entitled to receive from the Company or an
affiliate, would constitute an excess "parachute payment" within the meaning of
Section 280G of the Internal Revenue Code of 1986, as amended (the "Code"), the
payments and benefits provided under this Agreement shall be reduced to the
extent necessary so that no portion thereof shall fail to be tax-deductible
under Section 280G of the Code.

         IN WITNESS WHEREOF, the parties hereto have signed their names as of
the day and year first above written.
BY:  COMPANY


By: /s/ Thomas Rambold                  By: /s/ Roland Koch
        --------------                      ---------------
Name:   Thomas Rambold                  Name:   Roland Koch



BY:  EMPLOYEE


By: /s/ Martin Clague
    -----------------
Name:   Martin Clague




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