1998 STOCK PLAN

Exhibit 4.2


NBX CORPORATION


1998 STOCK PLAN


1. Purpose. The purpose of the NBX Corporation 1998 Stock Plan (the "Plan") is to encourage key employees of NBX Corporation (the "Company") and of any present or future parent or subsidiary of the Company (collectively, "Related Corporations") and other individuals who render services to the Company or a Related Corporation, by providing opportunities to participate in the ownership of the Company and its future growth through (a) the grant of options which qualify as "incentive stock options" ("ISOs") under Section 422(b) of the Internal Revenue Code of 1986, as amended (the "Code"); (b) the grant of options which do not qualify as ISOs ("Non-Qualified Options"); (c) awards of stock in the Company ("Awards"); and (d) opportunities to make direct purchases of stock in the Company ("Purchases"). Both ISOs and Non-Qualified Options are referred to hereafter individually as an "Option" and collectively as "Options." Options, Awards and authorizations to make Purchases are referred to hereafter collectively as "Stock Rights." As used herein, the terms "parent" and "subsidiary" mean "parent corporation" and "subsidiary corporation," respectively, as those terms are defined in Section 424 of the Code.


2. Administration of the Plan.


A. Board or Committee Administration. The Plan shall be
administered by the Board of Directors of the Company (the "Board") or,
subject to Paragraph 2D (relating to compliance with Section 162(m) of
the Code), by a committee appointed by the Board (the "Committee").
Hereinafter, all references in this Plan to the "Committee" shall mean
the Board if no Committee has been appointed. Subject to ratification
of the grant or authorization of each Stock Right by the Board (if so
required by applicable state law), and subject to the terms of the
Plan, the Committee shall have the authority to (i) determine to whom
(from among the class of employees eligible under paragraph 3 to
receive ISOs) ISOs shall be granted, and to whom (from among the class
of individuals and entities eligible under paragraph 3 to receive
Non-Qualified Options and Awards and to make Purchases) Non-Qualified
Options, Awards and authorizations to make Purchases may be granted;
(ii) determine the time or times at which Options or Awards shall be
granted or Purchases made; (iii) determine the purchase price of shares
subject to each Option or Purchase, which prices shall not be less than
the minimum price specified in paragraph 6; (iv) determine whether each
Option granted shall be an ISO or a Non-Qualified Option; (v) determine
(subject to paragraph 7) the time or times when each Option shall
become exercisable and the duration of the exercise period; (vi) extend
the period during which outstanding Options may be exercised; (vii)
determine whether restrictions such as repurchase options are to be
imposed on shares subject to Options, Awards and Purchases and the
nature of such restrictions, if any, and (viii) interpret the Plan and
prescribe and rescind rules and regulations relating to it. If the
Committee determines to issue a Non-Qualified Option, it shall take
whatever actions it deems necessary, under Section 422 of the Code and
the regulations promulgated thereunder, to ensure that such Option is
not treated as an ISO. The interpretation and construction by the
Committee of any provisions of the Plan or of any Stock Right granted
under it shall be final unless otherwise determined by the Board. The
Committee may from time to time adopt such rules and regulations for
carrying out the Plan as it may deem advisable. No member of the Board
or the Committee shall be liable for any action or determination made
in good faith with respect to the Plan or any Stock Right granted under
it.


B. Committee Actions. The Committee may select one of its
members as its chairman, and shall hold meetings at such time and
places as it may determine. A majority of the Committee shall
constitute a quorum and acts of a majority of the members of the
Committee at a meeting at which a quorum is present, or acts reduced to
or approved in writing by all the members of the Committee (if
consistent with applicable state law), shall be the valid acts of the
Committee. From time to time the Board may increase the size of the
Committee and appoint additional members thereof, remove members (with
or without cause) and appoint new members in substitution therefor,
fill vacancies however caused, or remove all members of the Committee
and thereafter directly administer the Plan.


C. Grant of Stock Rights to Board Members. Stock Rights may be
granted to members of the Board. All grants of Stock Rights to members
of the Board shall in all respects be made in accordance with the
provisions of this Plan applicable to other eligible persons. Members
of the Board who either (i) are eligible to receive grants of Stock
Rights pursuant to the Plan or (ii) have been granted Stock Rights may
vote on any matters affecting the administration of the Plan or the
grant of any Stock Rights pursuant to the Plan, except that no such
member shall act upon the granting to himself or herself of Stock
Rights, but any such member may be counted in determining the existence
of a quorum at any meeting of the Board during which action is taken
with respect to the granting to such member of Stock Rights.


D. Performance-Based Compensation. The Board, in its
discretion, may take such action as may be necessary to ensure that
Stock Rights granted under the Plan qualify as "qualified
performance-based compensation" within the meaning of Section 162(m) of
the Code and applicable regulations promulgated thereunder
("Performance-Based Compensation"). Such action may include, in the
Board's discretion, some or all of the following (i) if the Board
determines that Stock Rights granted under the Plan generally shall
constitute Performance-Based Compensation, the Plan shall be
administered, to the extent required for such Stock Rights to
constitute Performance-Based Compensation, by a Committee consisting
solely of two or more "outside directors" (as defined in applicable
regulations promulgated under Section 162(m) of the Code), (ii) if any
Non-Qualified Options with an exercise price less than the fair market
value per share of Common Stock are granted under the Plan and the
Board determines that such Options should constitute Performance-Based
Compensation, such options shall be made exercisable only upon the
attainment of a pre-established, objective performance goal established
by the Committee, and such grant shall be submitted for, and shall be
contingent upon shareholder approval and (iii) Stock Rights granted
under the Plan may be subject to such other terms and conditions as are
necessary for compensation recognized in connection with the exercise
or disposition of such Stock Right or the disposition of Common Stock
acquired pursuant to such Stock Right, to constitute Performance-Based
Compensation.


3. Eligible Employees and Others. ISOs may be granted only to employees of the Company or any Related Corporation. Non-Qualified Options, Awards and authorizations to make Purchases may be granted to any employee, officer or director (whether or not also an employee) or consultant of the Company or any Related Corporation. The Committee may take into consideration a recipient's individual circumstances in determining whether to grant a Stock Right. The granting of any Stock Right to any individual or entity shall neither entitle that individual or entity to, nor disqualify such individual or entity from, participation in any other grant of Stock Rights.


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4. Stock. The stock subject to Stock Rights shall be authorized but unissued shares of Common Stock of the Company, par value $.001 per share (the "Common Stock"), or shares of Common Stock reacquired by the Company in any manner. The aggregate number of shares which may be issued pursuant to the Plan is 400,000, subject to adjustment as provided in paragraph 13. If any Option granted under the Plan shall expire or terminate for any reason without having been exercised in full or shall cease for any reason to be exercisable in whole or in part or shall be repurchased by the Company, the unpurchased shares of Common Stock subject to such Option shall again be available for grants of Stock Rights under the Plan.


5. Granting of Stock Rights. Stock Rights may be granted under the Plan at any time on or after May 19, 1998 and prior to May 19, 2009. The date of grant of a Stock Right under the Plan will be the date specified by the Committee at the time it grants the Stock Right; provided, however, that such date shall not be prior to the date on which the Committee acts to approve the grant.


6. Minimum Option Price; ISO Limitations.


A. Price for Non-Qualified Options, Awards and Purchases.
Subject to Paragraph 2D (relating to compliance with Section 162(m) of
the Code), the exercise price per share specified in the agreement
relating to each Non-Qualified Option granted, and the purchase price
per share of stock granted in any Award or authorized as a Purchase,
under the Plan may be less than the fair market value of the Common
Stock of the Company on the date of grant; provided that, in no event
shall such exercise price or such purchase price be less than the
minimum legal consideration required therefor under the laws of any
jurisdiction in which the Company or its successors in interest may be
organized.


B. Price for ISOs. The exercise price per share specified in
the agreement relating to each ISO granted under the Plan shall not be
less than the fair market value per share of Common Stock on the date
of such grant. In the case of an ISO to be granted to an employee
owning stock possessing more than ten percent (10%) of the total
combined voting power of all classes of stock of the Company or any
Related Corporation, the price per share specified in the agreement
relating to such ISO shall not be less than one hundred ten percent
(110%) of the fair market value per share of Common Stock on the date
of grant. For purposes of determining stock ownership under this
paragraph, the rules of Section 424(d) of the Code shall apply. The
date of grant for purposes of this subparagraph shall mean the date
that the Company or Related Corporation completes the corporate action
constituting an offer of stock for sale to an individual.


C. $100,000 Annual Limitation on ISO Vesting. Each eligible
employee may be granted Options treated as ISOs only to the extent
that, in the aggregate under this Plan and all incentive stock option
plans of the Company and any Related Corporation, ISOs do not become
exercisable for the first time by such employee during any calendar
year with respect to stock having a fair market value (determined at
the time the ISOs were granted) in excess of $100,000. The Company
intends to designate any Options granted in excess of such limitation
as Non-Qualified Options, and the Company shall issue separate
certificates to the optionee with respect to Options that are
Non-Qualified Options and Options that are ISOs.


D. Determination of Fair Market Value. If, at the time an
Option is granted under the Plan, the Company's Common Stock is
publicly traded, "fair market value" shall be determined as of the date
of grant or, if the prices or quotes discussed in this sentence are
unavailable for such date,


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the last business day for which such prices or quotes are available
prior to the date of grant and shall mean (i) the average (on that
date) of the high and low prices of the Common Stock on the principal
national securities exchange on which the Common Stock is traded, if
the Common Stock is then traded on a national securities exchange; or
(ii) the last reported sale price (on that date) of the Common Stock on
the Nasdaq National Market, if the Common Stock is not then traded on a
national securities exchange; or (iii) the closing bid price (or
average of bid prices) last quoted (on that date) by an established
quotation service for over-the-counter securities, if the Common Stock
is not reported on the Nasdaq National Market. If the Common Stock is
not publicly traded at the time an Option is granted under the Plan,
"fair market value" shall mean the fair value of the Common Stock as
determined by the Committee after taking into consideration all factors
which it deems appropriate, including, without limitation, recent sale
and offer prices of the Common Stock in private transactions negotiated
at arm's length.


7. Option Duration. Subject to earlier termination as provided in paragraphs 9 and 10 or in the agreement relating to such Option, each Option shall expire on the date specified by the Committee, but not more than (i) ten years from the date of grant in the case of Options generally and (ii) five years from the date of grant in the case of ISOs granted to an employee owning stock possessing more than ten percent (10%) of the total combined voting power of all classes of stock of the Company or any Related Corporation, as determined under paragraph 6(B). Subject to earlier termination as provided in paragraphs 9 and 10, the term of each ISO shall be the term set forth in the original instrument granting such ISO, except with respect to any part of such ISO that is converted into a Non-Qualified Option pursuant to paragraph 16.


8. Exercise of Option. Subject to the provisions of paragraphs 9 through 12 and paragraph 21, each Option granted under the Plan shall be exercisable as follows:


A. Vesting. The Option shall either be fully exercisable on
the date of grant or shall become exercisable thereafter in such
installments as the Committee may specify.


B. Full Vesting of Installments. Once an installment becomes
exercisable, it shall remain exercisable until expiration or
termination of the Option, unless otherwise specified by the Committee.


C. Partial Exercise. Each Option or installment may be
exercised at any time or from time to time, in whole or in part, for up
to the total number of shares with respect to which it is then
exercisable.


D. Acceleration of Vesting. The Committee shall have the right
to accelerate the date that any installment of any Option becomes
exercisable; provided that the Committee shall not, without the consent
of an optionee, accelerate the permitted exercise date of any
installment of any Option granted to any employee as an ISO (and not
previously converted into a Non-Qualified Option pursuant to paragraph
16) if such acceleration would violate the annual vesting limitation
contained in Section 422(d) of the Code, as described in paragraph
6(C).


9. Termination of Employment. Unless otherwise specified in this Plan or the agreement relating to such ISO, if an ISO optionee ceases to be employed by the Company and all Related Corporations other than by reason of death or disability as defined in paragraph 10, no further installments of his or her ISOs shall become exercisable, and his or her ISOs shall terminate on the earlier of (a) three months after the date of termination of his or her employment, or (b) their specified expiration dates, except to the extent that


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such ISOs (or unexercised installments thereof) have been converted into Non-Qualified Options pursuant to paragraph 16. For purposes of this paragraph 9, employment shall be considered as continuing uninterrupted during any bona fide leave of absence (such as those attributable to illness, military obligations or governmental service) provided that the period of such leave does not exceed 90 days or, if longer, any period during which such optionee's right to reemployment is guaranteed by statute or by contract. A bona fide leave of absence with the written approval of the Committee shall not be considered an interruption of employment under this paragraph 9, provided that such written approval contractually obligates the Company or any Related Corporation to continue the employment of the optionee after the approved period of absence. ISOs granted under the Plan shall not be affected by any change of employment within or among the Company and Related Corporations, so long as the optionee continues to be an employee of the Company or any Related Corporation. Nothing in the Plan shall be deemed to give any grantee of any Stock Right the right to be retained in employment or other service by the Company or any Related Corporation for any period of time.


10. Death; Disability.


A. Death. If an ISO optionee ceases to be employed by the
Company and all Related Corporations by reason of his or her death, any
ISO owned by such optionee may be exercised, to the extent otherwise
exercisable on the date of death, by the estate, personal
representative or beneficiary who has acquired the ISO by will or by
the laws of descent and distribution, until the earlier of (i) the
specified expiration date of the ISO or (ii) 180 days from the date of
the optionee's death.


B. Disability. If an ISO optionee ceases to be employed by the
Company and all Related Corporations by reason of his or her
disability, such optionee shall have the right to exercise any ISO held
by him or her on the date of termination of employment, for the number
of shares for which he or she could have exercised it on that date,
until the earlier of (i) the specified expiration date of the ISO or
(ii) 180 days from the date of the termination of the optionee's
employment. For the purposes of the Plan, the term "disability" shall
mean "permanent and total disability" as defined in Section 22(e)(3) of
the Code or any successor statute.


11. Assignability. No ISO shall be assignable or transferable by the optionee except by will or by the laws of descent and distribution, and during the lifetime of the optionee shall be exercisable only by such optionee. Stock Rights other than ISOs shall be transferable to the extent set forth in the agreement relating to such Stock Right.


12. Terms and Conditions of Options. Options shall be evidenced by instruments (which need not be identical) in such forms as the Committee may from time to time approve. Such instruments shall conform to the terms and conditions set forth in paragraphs 6 through 11 hereof and may contain such other provisions as the Committee deems advisable which are not inconsistent with the Plan, including restrictions applicable to shares of Common Stock issuable upon exercise of Options. The Committee may specify that any Non-Qualified Option shall be subject to the restrictions set forth herein with respect to ISOs, or to such other termination and cancellation provisions as the Committee may determine. The Committee may from time to time confer authority and responsibility on one or more of its own members and/or one or more officers of the Company to execute and deliver such instruments. The proper officers of the Company are authorized and directed to take any and all action necessary or advisable from time to time to carry out the terms of such instruments.


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13. Adjustments. Upon the occurrence of any of the following events, an optionee's rights with respect to Options granted to such optionee hereunder shall be adjusted as hereinafter provided, unless otherwise specifically provided in the written agreement between the optionee and the Company relating to such Option:


A. Stock Dividends and Stock Splits. If the shares of Common
Stock shall be subdivided or combined into a greater or smaller number
of shares or if the Company shall issue any shares of Common Stock as a
stock dividend on its outstanding Common Stock, the number of shares of
Common Stock deliverable upon the exercise of Options shall be
appropriately increased or decreased proportionately, and appropriate
adjustments shall be made in the purchase price per share to reflect
such subdivision, combination or stock dividend.


B. Consolidations or Mergers. If the Company is to be
consolidated with or acquired by another entity by sale or transfer of
capital stock or in a merger or other reorganization and as a result of
such sale or transfer, merger or reorganization the holders of the
outstanding voting stock of the Company immediately preceding the
consummation of such event, shall, immediate ...