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                                                                    Exhibit 10.6

                              EMPLOYMENT AGREEMENT


         EMPLOYMENT AGREEMENT dated as of March 14, 1999, by and between
Redstone Communications, Inc. with its principal place of business at 5 Carlisle
Road, Westford, Massachusetts 01886 (the "Company"), and Kurt Melden residing at
____________________ (the "Executive").

         WHEREAS, pursuant to an Agreement and Plan of Merger dated as of March
14, 1999 (the "Merger Agreement") among Siemens Corporation, a Delaware
corporation ("Siemens"), Wolf Acquisition Corp., a Delaware corporation
("Acquisition"), and the Company, Acquisition shall be merged with and into the
Company (the "Merger") and the Company shall be the surviving corporation in the
Merger.

         WHEREAS, the Executive's stock and other equity interests in the
Company shall be acquired by Siemens in connection with the Merger.

         WHEREAS, the Executive has been employed by the Company, and the
Company wishes to offer continuing employment to the Executive in connection
with the Merger 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 the Closing Date
(as defined in the Merger Agreement) and ending on the second anniversary of
such date, 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 30
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 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
attached hereto as Exhibits A and B, respectively.

2. DUTIES. During the Term, the Executive shall be employed by the Company as
Vice President of Technology 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
consistent with such office as shall be specified and designated from time to
time by the Board of Directors of the Company. The Executive shall devote
substantially all of his business time and effort to the performance of his
duties hereunder.

3.       COMPENSATION.

         3.1 BASE SALARY. The Company shall pay the Executive during the Term a
base salary at the rate of $126,000 per annum (the "Annual Salary"), in
accordance with the customary payroll practices of the Company applicable to
senior executives. The Annual Salary shall be reviewed at least annually by the
Compensation Committee of the Board of Directors of the Company, but shall not
be decreased.


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         3.2 BONUS. During the Term, in addition to the Annual Salary, the
Executive shall participate in the Company's Milestone Incentive Compensation
Plan and shall have the opportunity to receive an annual bonus based on the
achievement of certain performance measures.

         3.3 BENEFITS - IN GENERAL. The Executive shall be entitled during the
Term to participate in group life, hospitalization or disability insurance
plans, health programs, retirement plans, fringe benefit programs and similar
benefits that may be available to other senior 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,
which plans and programs shall generally provide a level of benefits that is at
least as favorable as the benefits provided by the Company on the date hereof.

         3.4 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 ordinary
policies of the Company with respect to reimbursement of senior executives 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 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 any Annual Salary and other benefits 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); (ii) the
Executive shall have a non-forfeitable right to, and shall be entitled to
receive, the consideration payable to the Executive under the Merger Agreement
with respect to which the Executive's rights were not vested at Closing (as
defined in the Merger Agreement) and which has not yet been paid as of the date
of termination; (iii) the Executive (or the Executive's estate or beneficiaries
in the case of the death of the Executive) shall be entitled to receive all
payments that he would have received under the Company's Milestone Incentive
Plan if he had remained employed through the Performance Period (as defined in
the Milestone Incentive Plan) and (iv) 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 except as required by law.

5.       CERTAIN TERMINATIONS OF EMPLOYMENT.

         5.1      TERMINATION BY THE COMPANY FOR CAUSE.

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

                           (i)      commission of a felony, a crime of moral
turpitude, dishonesty, 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;


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                           (iii) failure to follow directions of the Board of
Directors or to follow the Company's written policies and practices, which
failure is not cured within 30 days after written notice thereof is provided to
the Executive;

                           (iv) breach of either of the agreements attached
hereto as Exhibits A and B, which breach is not cured within 30 days after
written notice thereof is provided to the Executive; or

                           (v)      breach in any material respect of the terms
and provisions of this Agreement, which breach is not cured within 30 days after
written notice thereof is provided to the Executive; provided that the Company
shall not be permitted to terminate the Executive for Cause pursuant to Section
5.1(b) except on written notice given to the Executive.

                  (b) The Company may terminate the Executive's employment
hereunder for Cause. If the Company terminates the Executive for Cause, (i) the
Executive shall receive Annual Salary and other benefits (but, in all events,
and without increasing the Executive's rights under any other provision hereof,
excluding any bonuses 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 have no further rights to any other compensation or benefits
hereunder on or after the termination of employment, or any other rights
hereunder.

         5.2 TERMINATION BY THE COMPANY WITHOUT CAUSE; TERMINATION BY THE
EXECUTIVE FOR GOOD REASON.

                  (a) 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 Section 4 or 5.1 or the
Executive terminates service for "Good Reason", (i) the Executive shall receive
Annual Salary and other benefits earned and accrued under this Agreement and the
Company's Milestone Incentive Compensation Plan to the extent benefits are
earned, accrued and payable under the terms of such plan 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 100% of the Executive's Annual Salary (as in
effect immediately before such termination), payable no later than 15 days after
such termination and (B) for a period of 12 months after termination of
employment such continuing coverage under the group health plan and the basic
life insurance plan as the Executive was receiving at the time of such
termination of employment at the same cost to the Executive as that paid by
active executive-level employees; (iii) the Executive shall have a
non-forfeitable right to, and shall be entitled to receive, the consideration
payable to the Executive under the Merger Agreement with respect to which the
Executive's rights were not vested at Closing (as defined in the Merger
Agreement) and which has not yet been paid as of the date of termination; (iv)
the Executive shall be entitled to receive all payments that he would have
received under the Company's Milestone Incentive Plan if he had remained
employed through the Performance Period (as defined in the Milestone Incentive
Plan); and (v) the Executive shall have no further rights to any other
compensation or benefits hereunder on or after the termination of employment, or
any other rights hereunder; provided that the Company's obligations with respect
to the payments and benefits provided for in this Section 5.2(a) 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 5.2(a) shall be in lieu of any other payments that may
otherwise be due to the Executive under any severance or separation plan,
program or policy of the Company.

                  (b) For purposes of this Agreement, "Good Reason" shall mean
(i) a breach by the Company in any material respect of the terms and provisions
of this Agreement, which breach is not cured within 30 days after written notice
thereof is provided by the Executive or (ii) the relocation of the

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Company's principal place of business, without the consent of the Executive, by
more than 30 miles from such principal place of business on the date hereof.

                  (c) Notwithstanding clause (ii)(B) of the second sentence of
Section 5.2(a), (i) herein shall restrict the ability of the Company to amend or
terminate the plans and programs referred to in such clause (ii)(B) with respect
to employees of the Company generally from time to time in its sole discretion,
and (ii) the Company shall in no event be required to provide any benefits
otherwise required by such clause (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).

         5.3      TERMINATION BY THE EXECUTIVE OTHER THAN FOR GOOD REASON.

         The Executive may terminate his employment on at least 30 days' and not
more than 60 days' written notice given to the Company. If the Executive
terminates his employment and the termination is not covered by Section 4 or
5.2, (i) the Executive shall receive Annual Salary and other benefits (but, in
all events, and without increasing the Executive's rights under any other
provision hereof, excluding any bonuses 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 have no further rights to any other compensation or
benefits hereunder on or after the termination of employment, or any other
rights hereunder, except as required by law.

6.       OTHER PROVISIONS.

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

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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.

                  (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. Any decision or award of the arbitrator
shall be final, binding, and conclusive upon the parties and said decision and
award may e 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.

         6.3 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:

                          Redstone Communications, Inc.
                          5 Carlisle Road
                          Westford, Massachusetts 01886
                          Attention: Board of Directors

                          with a copy to:

                          Rogers & Wells LLP
                          200 Park Avenue
                          New York, New York 10166
                          Attention: John A. Healy, Esq.


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                  (ii)     If to the Executive, to the address set forth above.

                           with a copy to:

                           Hale and Dorr LLP
                           60 State Street
                           Boston, Massachusetts 02109
                           Attention: Mark G. Borden, Esq.

Any such person may by notice given in accordance with this Section 6.3 to the
other parties hereto designate another address or person for receipt by such
person of notices hereunder.

         6.4 ENTIRE AGREEMENT. Other than with respect to the agreements
attached hereto as Exhibits .A and B entered into by the Company and the
Executive dated as of the date hereof, as they may be amended from time to time,
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.

         6.5 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
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.

         6.6 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.

         6.7 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.

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

         6.9 BINDING EFFECT. This Agreement shall be binding upon and inure to
the benefit of the parties and their respective successors, permitted assigns,
heirs, executors and legal representatives.

         6.10 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.

         6.11 SURVIVAL. Anything contained in this Agreement to the contrary
notwithstanding, the provisions of Sections 6.2, 6.3 and 6.8, and the other
provisions of this Section 6 (to the extent necessary

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to effectuate the survival of Sections 6.2, 6.3 and 6.8), shall survive
termination of this Agreement and any termination of the Executive's employment
hereunder.

         6.12 NON-DISPARAGEMENT. While Executive's non-competition obligations
under Exhibit A are in effect, the Executive shall not publish any statement or
make any statement under circumstances reasonably likely to become public that
is critical of the Company or any of its affiliates, or in any way adversely
affecting or otherwise maligning the Company's business or the reputation of the
Company or of its affiliates.

         6.13 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.

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

         6.15 EFFECTIVE DATE. Notwithstanding, anything to the contrary herein,
this Agreement shall become effective only upon the Effective Time (as defined
in the Merger Agreement), and this Agreement shall automatically be void upon
any termination of the Merger Agreement prior to the Effective Time.

                         [SIGNATURES ON FOLLOWING PAGE]




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

                                           REDSTONE COMMUNICATIONS, INC.


                                           By: /s/James A. Dolce, Jr.


                                           Name: James A. Dolce, Jr.


                                           Title: President & Treasurer


                                           By: /s/ Kurt Melden
                                               __________________________
                                                    Executive




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