Document:

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                                                                EXHIBIT NO. 10.6

                            MCK COMMUNICATIONS, INC.
                              INCENTIVE BONUS PLAN

     1.  PURPOSE. The purpose of this MCK Communications, Inc. Incentive Bonus
Plan (this "PLAN") is to enhance shareholder value by providing key members of
management of MCK Communications, Inc., a Delaware corporation (the "COMPANY"),
with greater incentive to remain in the employ of the Company through the
effective date of a Change in Control (as defined in Section 3 below) and, if
requested by any successor to the Company, to remain in the employ of such
successor for a period of six (6) months following such effective date.

     2.  ELIGIBILITY. An employee of the Company shall be eligible to
participate in this Plan only upon his or her designation by the Administrator
(as defined in Section 3 below) as a participant in this Plan (each a
"PARTICIPANT") pursuant to a written resolution adopted by the Administrator and
delivered to such employee.

     3.  DEFINITIONS.

         (a) "ACCELERATED OPTION SHARES" means all shares of Common Stock
subject to stock options held by a Participant, the vesting of which is
accelerated (such that the stock options become exercisable to purchase such
shares of Common Stock for the first time) in connection with a Change in
Control.

         (b) "ACCELERATED RESTRICTED SHARES" means all shares of Common Stock
subject to stock restriction agreements or other similar arrangements held by a
Participant, the vesting of which is accelerated (such that any repurchase
rights in favor of the Company with respect any restricted or unvested shares
lapse for the first time) in connection with a Change in Control.

        (c) "ADMINISTRATOR" means the Compensation Committee of the Board.

        (d) "BOARD" means the Board of Directors of the Company or its successor
entity.

        (e) "BASE VALUATION OF THE COMPANY" means (i) in the case of a Change in
Control other than the sale of all or substantially all of the assets of the
Company, the aggregate value of the consideration to be paid or issued by the
third party acquiror in connection with such Change in Control in exchange for,
or in respect of, all of the outstanding shares of Common Stock and Common Stock
equivalents of the Company (including any consideration paid or issued after the
effective date pursuant to any escrow, earn out or other similar arrangement),
and (ii) in the case of the sale of all or substantially all of the assets of
the Company, the aggregate value of the consideration available for distribution
to the holders of Common Stock and Common Stock equivalents of the Company on
the effective date of such Change in Control on account of such holders'
ownership of such Common Stock and Common Stock equivalents (including amounts
so distributed after the effective date pursuant to any escrow, earn-out or

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other similar arrangement). The determination of the Base Valuation of the
Company shall be made by the Administrator, in its sole and absolute discretion.

        (f) "CAUSE" means: (i) any material breach by a Participant of any
agreement to which such Participant and the Company are parties, including, but
not limited to, any agreement containing covenants not to compete and covenants
relating to the protection of confidential information and proprietary rights of
the Company, which breach is not cured pursuant to the terms of such agreement,
(ii) any act or omission to act by a Participant which would reasonably be
likely to have the effect of injuring the reputation, business or business
relationships of the Company, (iii) a Participant's conviction (including any
pleas of guilty or nolo contendre) of any crime (other than ordinary traffic
violations) which impairs such Participant's ability to perform his or her
duties to the Company, (iv) any material misconduct or willful and deliberate
non-performance of duties by the Participant in connection with the business or
affairs of the Company, (v) a Participant's theft, dishonesty, misrepresentation
or falsification of the Company's documents or records, (vi) a Participant's
improper use or disclosure of the Company's confidential or proprietary
information, or (vii) a Participant's use of the facilities or premises of the
Company to conduct unlawful or unauthorized activities or transactions. For
purposes of this Section 3(f), the term "Company" shall include any affiliate or
successor of the Company. Notwithstanding anything contained in this Section
3(f) to the contrary, in the event that the term "cause" (or any other term of
similar import) is defined in any agreement between the Company and a
Participant (including any employment, stock option or stock restriction
agreement), the term "Cause" shall have the same meaning as specified in this
Plan for all purposes under this Plan with respect to such Participant
regardless of any other such definitions.

        (g) "CHANGE IN CONTROL" means the consummation of a: (i) a merger,
reorganization or consolidation of the Company with or into another person or
entity (other than a holding company or subsidiary of the Company), or any other
transaction or series of related transactions, as a result of which the holders
of the Company's outstanding voting stock immediately prior to the transaction
hold less than a majority of the outstanding voting stock of the surviving
entity immediately after the transaction or series of related transactions, or
(ii) the sale of all or substantially all of the assets of the Company to an
unrelated person or entity; provided, however, that the commencement of
bankruptcy proceedings by or against the Company shall not constitute a "Change
in Control" for purposes of this Plan.

        (h) "COMMON STOCK" means the common stock of the Company, par value
$.001 per share.

        (i) "COMMON STOCK SPREAD" means (i) with respect to any Accelerated
Option Shares, an amount equal to the value of the consideration to be received
in exchange for, or in respect of, one (1) share of Common Stock in connection
with a Change in Control MINUS the exercise price per share of such Accelerated
Option Shares, and (ii) with respect to any Accelerated Restricted Shares, an
amount equal to the value of the consideration to be received in exchange for,
or in respect of, one (1) share of Common Stock in connection with a Change in
Control MINUS the purchase price per share of such Accelerated Restricted
Shares. Notwithstanding the foregoing, the Common Stock Spread shall be deemed
to be zero (0) where the consideration to be received in exchange for one (1)
share of Common Stock in connection

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with a Change in Control is less than the applicable exercise or purchase price
per share of such Accelerated Option Shares or Accelerated Restricted Shares.

        (j) "INCENTIVE POOL" means the lesser of: (i) five percent (5%) of the
Base Valuation of the Company, or (ii) five million dollars ($5,000,000).

        (k) "OTHER CHANGE IN CONTROL PAYMENTS" means, with respect to each
Participant, an amount equal to:

                  x + y + z where:

                  (x)      is an aggregate amount equal to the Common
                           Stock Spread for each award of Accelerated
                           Option Shares held by such Participant
                           MULTIPLIED BY the total number of such
                           Accelerated Option Shares;

                  (y)      is an amount equal to the Common Stock
                           Spread for each award of Accelerated
                           Restricted Stock held by such Participant
                           MULTIPLIED BY the total number of such
                           Accelerated Restricted Stock; and

                  (z)      is the aggregate value of all other payments
                           and/or benefits that are or will be paid to
                           such Participant in connection with or as a
                           result of the Change in Control.

        (l) "PARTICIPATING PERCENTAGE" means with respect to each Participant,
the percentage interest in the Incentive Pool allocated to such Participant in a
written resolution adopted by the Administrator and delivered to such
Participant.

     4. EFFECTIVE DATE. This Plan is effective on March 26, 2002 (the "EFFECTIVE
DATE"), the date on which the Board approved this Plan.

     5. INCENTIVE BONUSES. Subject to the terms and conditions of this Plan,
each Participant who meets the eligibility conditions described in Section 6(a)
below shall become entitled to receive an incentive bonus under this Plan (each
an "INCENTIVE BONUS") in an amount equal to the difference of (a) such
Participant's Participating Percentage, MULTIPLIED BY the aggregate amount of
the Incentive Pool, MINUS (b) the aggregate amount of such Participant's other
Change in Control Payments; PROVIDED, HOWEVER, that in no event shall any
Participant be entitled to receive more than one million dollars ($1,000,000)
under this Plan.

     6. PAYMENT OF INCENTIVE BONUSES.

        (a)  ELIGIBILITY; TIMING OF PAYMENT.

                 (i)  Each Participant who remains in the employ of the Company
or its successor through the date which is six (6) months following the
effective date of the Change in Control shall become eligible to receive such
Participant's Incentive Bonus as of such date; provided, however, that any
Participant who is terminated by the Company or its successor

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without Cause on or within six (6) months after the effective date of the Change
of Control (or who voluntarily terminates their employment as a result of (x)
their annual base salary, target bonus and/or benefits being materially reduced
within six months after the effective date of the Change of Control from such
Participant's annual base salary, target bonus and/or benefits as in effect
immediately prior to the Change in Control or (y) their principal place of
employment being relocated within six (6) months after the effective date of the
Change of Control to a location more than fifty (50) miles from the location of
his or her principal place of employment immediately prior to the effective date
of the Change in Control) shall become eligible to receive such Participant's
Incentive Bonus as of the effective date of such termination.

                 (ii) Each Participant whose employment with the Company or its
successor is terminated for Cause after the effective date of a Change in
Control and prior to the date which is six months following the Change in
Control or who voluntarily resigns for any reason after the effective date of a
Change in Control and prior to the date which is six months following the Change
in Control shall upon such termination or resignation forfeit all right to any
portion of such Participant's Incentive Bonus as of the date of such termination
or resignation.

                 (iii) The Company or its successor shall pay each Participant
his or her Incentive Bonus within ten (10) business days after the date on which
such Participant satisfies the eligibility requirements described in this
Section 6(a) with respect such Incentive Bonus; provided, however, any portion
of the Incentive Bonus for which such Participant is eligible that is payable in
respect of Change in Control consideration payable after the effective date of
the Change in Control pursuant to any escrow, earn-out or other similar
arrangement shall be paid at the time the corresponding escrow, earn-out or
other similar payment is made to the holders of capital stock of the Company.

        (b) FORM OF PAYMENT. Payment of each Incentive Bonus shall be made via
a cash payment, regardless of the form of consideration that is paid in
connection with the Change in Control.

        (c) RELEASE. Notwithstanding the foregoing, the payment of any
Participant's Incentive Bonus shall be conditioned upon such Participant
executing a valid release, to be prepared by the Company, in which the
Participant shall release the Company and its respective officers, directors,
agents, employees, shareholders, owners, subsidiaries, affiliates, successors
and assigns (the "RELEASED PARTIES") from any claims that such Participant may
have against the Released Parties to the maximum extent permitted by law.

        (d) CERTIFICATION. The Administrator shall, in its sole and
absolute discretion, certify the date on which a Change in Control occurs and
the amount of each Incentive Bonus to be paid to each Participant pursuant to
this Plan.

     7. TERMINATION OF EMPLOYMENT PRIOR TO CHANGE IN CONTROL. Notwithstanding
anything contained in this Plan to the contrary, in the event that a
Participant's employment or service terminates prior to a Change in Control,
such Participant's participation in this Plan shall terminate immediately and
the Company shall not be obligated to make any payments to such Participant
pursuant to this Plan. Following any such termination, the

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Administrator may, in its sole and absolute discretion, reallocate the
terminated Participant's interest in the Incentive Pool, may reserve such
interest for future allocation to other Participants or may retire such
interest.

     8. EXCISE TAX GROSS-UP PAYMENT. If it shall be determined that any payment
to a Participant pursuant to this Plan or any other payment or benefit made in
connection with a Change in Control by the Company, any affiliate of the Company
or any stockholder of the Company, would be subject to the excise tax imposed
under Section 4999 of the Internal Revenue Code of 1986, as amended, the Company
shall pay to such Participant, in addition to, and at the same time as, the
payment of the Participant's Incentive Bonus, an amount equal to the aggregate
amount of such excise tax required to be paid by the Participant with respect to
all such payments and benefits; provided, however, that in all events any
payment under this Section shall be capped at a maximum amount equal to twenty
percent (20%) of the Participant's Incentive Bonus. The foregoing shall be
conditioned on the Participant cooperating with the Company in such manner as
may be reasonable requested (other than reducing amounts payable hereunder) so
as to minimize the amount of such excise tax. Unless the Participant and the
Company otherwise agree in writing, any determination required under this
Section 8 shall be made in writing by an independent public accounting firm
agreed to by the Participant and the Company, whose determination shall be final
and binding upon the Participant and the Company for all purposes. The Company
shall bear all costs reasonably incurred in connection with any calculations
contemplated by this Section 8, including, but not limited to, accountants and
attorneys fees.

     9. WITHHOLDING. The Company shall deduct from any payments made pursuant to
this Plan an amount equal to all or any part of the federal, state, local and
foreign taxes, if any, required by law to be withheld by the Company with
respect to such payments.

     10. NON-ASSIGNABILITY. No Participant shall have the power or right to
transfer, assign, anticipate, mortgage or otherwise encumber his or her interest
under this Plan; nor shall such interest be subject to seizure for the payment
of a Participant's debts, judgments, alimony or separate maintenance or be
transferable by operation of law in the event of a Participant's bankruptcy,
insolvency, divorce or separation. This Plan shall be binding upon and shall
inure to the benefit of the Company and its successors and assigns and, upon a
Change in Control, the Company shall require its successor(s) or assign(s) to
expressly assume and agree to perform its obligations under this Plan, in the
same manner and to the same extent that the Company would be required to perform
it as if no such succession or assignment had taken place.

     11. TERMINATION AND AMENDMENT OF THE PLAN. The Administrator may amend or
terminate this Plan at any time; PROVIDED THAT, upon and after the effectiveness
of a Change in Control, no termination or amendment of this Plan shall, without
the consent of a Participant, impair the rights of such Participant, unless such
termination or amendment of this Plan is made in compliance with a law or
regulation applicable to this Plan or is required to avoid any penalties or
excise taxes relating to such laws or regulations. Unless terminated earlier by
the Administrator, this Plan shall terminate on the earlier to occur of: (i) the
final payment of the Incentive Bonus to each person who is a Participant upon
the effectiveness of a Change in Control, or (ii) the third (3rd) annual
anniversary of the Effective Date, in either of which event,

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neither the Company nor its successors, assigns or affiliates shall thereafter
have any liability or other obligation to the Participants.

     12. ADMINISTRATION. The Administrator shall have the power from time to
time: (i) to construe and interpret this Plan and to establish, amend and revoke
rules and regulations for the administration of this Plan (including, but not
limited to, correcting any defect, supplying any omission, or reconciling any
inconsistency in this Plan) in the manner and to the extent it shall deem
necessary or advisable to make this Plan fully effective; (ii) to exercise its
discretion with respect to the powers and rights granted to it as set forth in
this Plan; and (iii) generally, to exercise such powers and to perform such acts
as are deemed necessary or advisable to promote the best interests of the
Company with respect to this Plan. All decisions and interpretations of the
Administrator relating to this Plan shall be binding on all persons, including
the Company, the Company's stockholders and all Participants. The Administrator,
and all agents of the Administrator, shall not be personally liable for any
action, omission, determination or interpretation made in good faith with
respect to this Plan, and the Administrator, and all agents of the
Administrator, shall be fully indemnified by the Company with respect to any
claim, loss, damage, or expense arising from such action, omission,
determination or interpretation to the full extent permitted by law.

     13. LIMITATION OF LIABILITY. Nothing contained in this Plan, and no action
taken pursuant to its provisions, shall create or be construed to create a
fiduciary relationship between the Company (or any person connected therewith)
and any Participant, employee or other person. In no event shall the Company (or
any person connected therewith) be liable to any person for the failure of any
Participant to be entitled to any particular tax consequences with respect to
this Plan or distribution therefrom.

     14. EMPLOYMENT RIGHTS. The adoption of this Plan does not confer upon any
Participant any right to continued employment or service with the Company or
interfere in any way with the right of the Company to terminate the
Participant's employment or service at any time.

     15. EFFECT ON OTHER BENEFITS. Any payments made pursuant to this Plan shall
not be counted as compensation for purposes of any other employee benefit plan,
program or agreement sponsored, maintained or contributed to by the Company
unless expressly provided for in such employee benefit plan, program or
agreement.

     16. UNFUNDED, UNSECURED OBLIGATION. This Plan shall at all times be
entirely unfunded and no provisions shall at any time be made with respect to
segregating assets of the Company for payment of any benefits hereunder.
Additionally, nothing contained herein shall be construed as giving a
Participant, his or her beneficiary or any other person, any equity or other
interest of any kind in any assets of the Company or creating a trust of any
kind or a fiduciary relationship of any kind between the Company and any such
person. As to any claim for any unpaid amounts under this Plan, a Participant,
his or her beneficiary and any other person having a claim for payment shall be
unsecured creditors.

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     17. NON-EXCLUSIVE. Adoption of this Plan shall not be construed as creating
any limitations on the power of the Company to adopt such other incentive
arrangements as it may deem desirable.

     18. SEVERABILITY. If any provision of this Plan shall be determined to be
illegal or unenforceable, such determination shall in no manner affect the
legality or enforceability of any other provision hereof.

     19. HEADINGS. The headings used herein are intended only for convenience in
finding the subject matter and do not constitute part of the text of this Plan
and shall not be considered in the interpretation of this Plan.

     20. GOVERNING LAW. This Plan shall be governed by and construed in
accordance with the laws of the State of Delaware, without regard to the
conflict of law principles thereof.

                                       7<PAGE>
                                                                   Exhibit 10.12

THIS SECURITY HAS NOT BEEN REGISTERED UNDER THE SECURITIES ACT OF 1933, AS
AMENDED, AND MAY NOT BE SOLD, ASSIGNED OR OTHERWISE TRANSFERRED IN THE ABSENCE
OF SUCH REGISTRATION OR AN EXEMPTION FROM SUCH REGISTRATION.

                                 PROMISSORY NOTE
                                 ---------------

                                                          Needham, Massachusetts
                                                                  March 13, 2001

US$253,020

     FOR VALUE RECEIVED, the undersigned ("DEBTOR") hereby promises to pay to
MCK Communications, Inc., a Delaware corporation, or its successor ("Payee"), at
such place or places as may be specified by Payee or any holder hereof, in legal
tender of the United States of America, the principal amount of $253,020 (the
"PRINCIPAL"), which represents the amount equal to the fair market value of the
shares of Common Stock purchased on the date hereof from the Company less the
par value of such shares (which was paid to the Company in cash), with interest
at the fixed rate of 5.58% per annum, compounded annually, on the unpaid
balance. Interest shall be payable on each anniversary of the date hereof. The
Principal, with accrued interest thereon, shall become due and payable in whole
or in part upon any sale by the Debtor of shares of Common Stock, $.001 par
value, of the Payee ("COMMON STOCK") pursuant to the terms set forth below. In
any event, any Principal then unpaid shall be due and payable, with accrued
interest thereon, on the fourth (4th) anniversary of the date hereof (the
"REPAYMENT DATE"). The Debtor shall pay to Payee, within ten (10) days after
receipt thereof, the net after-tax proceeds from any sales by the Debtor of
shares of the Common Stock of the Payee held or being acquired on the date
hereof, or any successor securities, in reduction of the Principal until such
time as the Principal has been paid in full, and in connection with each such
payment shall pay accrued but unpaid interest on the amount so paid. For
purposes hereof, net after-tax proceeds refers to the amount received upon any
sale of such shares, less brokerage commissions or underwriting discounts, other
expenses of every kind, including documentary, excise and other taxes, if any,
directly relating to the sale and an amount equal to the federal, state and
local taxes on any gain from such sale (as determined by multiplying the amount
of such gain by the combined maximum federal, state and local tax rate
applicable to the sale of such shares by the Debtor, taking into account the
holding period for such shares and any federal income tax deduction for state
and local income taxes).

     A default (an "EVENT OF DEFAULT") shall be deemed to have occurred
hereunder if (a) Debtor fails in any material respect to perform any material
obligation hereunder, if any material representation or warranty hereunder was
untrue in any material respect when made, or if any default or Event of Default
by Debtor occurs under this Note or any agreement evidencing, or constituting or
granting security for, the Debtor's obligations, and (b) the Company gives to
Debtor written notice thereof and such default shall not have been cured within
fourteen (14) days or such additional time as may be required to effect such
cure if diligently pursued.

     In case an Event of Default shall occur, the aggregate unpaid balance of
Principal and accrued interest thereon may be declared to be due and payable in
the manner and with the effect as set forth below. The Payee shall have full
recourse against any assets of the Debtor in connection with the repayment of
the accrued interest on the Principal and up to the Recourse Amount (as
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hereinafter defined) against any assets of the Debtor. The Recourse Amount as of
any time shall mean (i) 30% of the Principal amount hereof reduced by 30% of
each payment of Principal made by or on behalf of the Debtor from any source and
(ii) the full amount of accrued interest under this Note (it being understood
that the Debtor shall be personally obligated for the payments of interest
hereunder). Unless otherwise directed by the Debtor, all sums paid by the Debtor
or otherwise received by Payee on account of sums owing hereunder shall be
deemed to reduce the Recourse Amount on a proportionate basis.

     Upon and after the occurrence of any Event of Default which is then
continuing or which has not been cured within the time period given for such
cure

          (a)  The Company may demand, sue for collection or make any other
compromise or settlement with respect to other rights and remedies provided for
herein or otherwise available to it, and the Company shall have all of the
rights and remedies of a secured party in Massachusetts under the Uniform
Commercial Code.

          (b)  Except as specifically reserved herein, Debtor waives all
suretyship defenses at law and in equity, and further waives the requirement of
any demand and presentment.

     Except as otherwise provided herein or by law, Debtor waives presentment,
demand, notice and protest, notice of acceptance of this Agreement. No failure
by the Company to exercise, no delay by the Company in exercising, and no single
or partial exercise of, any right, remedy or power hereunder or under any other
agreement relating to the obligations of the Debtor shall operate as a waiver
thereof, or of any other right, remedy or power at any time.

     Except as provided herein, Debtor may not prepay any of the principal
balance hereof or accrued interest thereon.

     Debtor expressly waives presentment for payment, protest and demand, notice
of protest, demand and dishonor and expressly agrees that this Note may be
extended from time to time without in any way affecting the liability of Debtor.
No delay or omission on the part of Payee in exercising any right hereunder
shall operate as a waiver of such right or of any other right under this Note.

     This Note may from time to time be extended by Payee, with or without
notice to Debtor, and any related right may be waived, exchanged, surrendered or
otherwise dealt with, all without affecting the liability of Debtor, in each
case in the sole discretion of Payee.

     This Note may be changed, modified or terminated only by an agreement in
writing and signed by the Debtor and Payee. This Note shall be governed by and
construed in accordance with the laws The Commonwealth of Massachusetts, and
shall be binding upon the successors and assigns of Debtor and inure to the
benefit of Payee and its successors, endorsees and assigns.

                                             DEBTOR:

                                             /s/ Glenda Davis
                                             -----------------------------------
                                             Name:  Glenda Davis

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