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                                                                     EXHIBIT 4.1

                                  CAMBIO, INC.
                                 2000 STOCK PLAN


     1. Purpose. The purpose of the Cambio 2000 Stock Plan (the "Plan") is to
establish a flexible vehicle through which Cambio Inc., a Delaware corporation
(the "Company"), can award stock or stock options to eligible personnel of the
Company in order to attract, retain and motivate such personnel and to further
align the interests of such personnel with those of the stockholders of the
Company.


     2. Types of Awards. Awards under the Plan may be in the form of shares of
the Company's common stock, par value $0.01 per share ("Common Stock") or
options to purchase shares of Common Stock, including options intended to
qualify as "incentive stock options" ("ISOs") within the meaning of Section 422
of the Internal Revenue Code of 1986, as amended (the "Code") and options which
do not qualify as ISOs ("NQSOs").

     3. Administration.

        (a) Committee. The Plan shall be administered by the Board of Directors
of the Company (the "Board") or a committee or subcommittee thereof (the
"Committee") appointed by the Board. To the extent that the Plan is administered
by the Board, the Board shall have all of the authority and responsibility
granted to the Committee herein. If a committee is appointed hereunder, then,
unless the Board determines otherwise, its members shall consist solely of
individuals who qualify as "non-employee directors" under Rule 16b-3 promulgated
under the Securities Exchange Act of 1934, as amended (the "Exchange Act"), and
as "outside directors" under Section 162(m) of the Internal Revenue Code of 1986
(the "Code"). If for any reason the Committee does not satisfy the "non-employee
director" requirements of Rule 16b-3 or the "outside director" requirements of
Section 162(m) of the Code, such non-compliance shall not affect the validity of
the awards, interpretations or other actions of the Committee. Notwithstanding
anything herein to the contrary, the Plan shall be administered by the Board
with respect to grants of awards to non-employee directors of the Company.

        (b) Authority of Committee. Subject to the limitations of the Plan, the
Committee, acting in its sole and absolute discretion, shall have full power and
authority to (i) select the persons to whom awards shall be made under the Plan,
(ii) make awards to such persons and prescribe the terms and conditions of such
awards, (iii) construe, interpret and apply the provisions of the Plan and of
any agreement or other document evidencing an award made under the Plan, (iv)
prescribe, amend and rescind rules and regulations relating to the Plan,
including rules governing its own operations, (v) correct any defect, supply any
omission and reconcile any inconsistency in the Plan, (vi) amend any outstanding
award in any respect, including, without limitation, to accelerate the time or
times at which the award becomes vested, (vii) carry out any responsibility or
duty specifically reserved to the Committee under the Plan, and (viii) make any
and all determinations and interpretations and take such other actions as may be
necessary or desirable in order to carry out



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the provisions, intent and purposes of the Plan. A majority of the members of
the Committee shall constitute a quorum. The Committee may act by the vote of a
majority of its members present at a meeting at which there is a quorum or by
unanimous written consent.

        (c) Indemnification. The Company shall indemnify and hold harmless each
member of the Committee and any employee or director of the Company to whom any
duty or power relating to the administration or interpretation of the Plan is
delegated from and against any loss, cost, liability (including any sum paid in
settlement of a claim with the approval of the Board), damage and expense
(including legal and other expenses incident thereto) arising out of or incurred
in connection with the Plan, unless and except to the extent attributable to
such person's, fraud or wilful misconduct.

     4. Share Limitations. Subject to adjustment pursuant to Section 13 below,
the maximum number of shares of Common Stock that may be issued under the Plan
is 5,000,000. For this purpose, the following shares shall be deemed not to have
been issued and shall be deemed to remain available for issuance: (i) shares
covered by the unexercised portion of an option that terminates, expires or is
canceled and (ii) shares that are withheld in order to pay the purchase price
for shares covered by any award or to satisfy the tax withholding obligations
associated with any award under the Plan. Shares of Common Stock available for
issuance under the Plan may be either authorized and unissued or held by the
Company in its treasury. No fractional shares of Common Stock shall be issued
under the Plan. The maximum number of shares of Common Stock with respect to
which awards may be granted under the Plan to any employee in any calendar year
shall be 1,000,000 shares.

     5. Eligibility. Awards under the Plan may be made to such officers,
directors, employees (including prospective employees), consultants and other
individuals who may perform services for the Company, as the Committee may
select. In making awards under the Plan, the Committee shall give consideration
to the functions and responsibilities of a potential recipient, the potential
recipient's previous and/or expected future contributions to the business of the
Company and such other factors as the Committee deems relevant under the
circumstances.

     6. Stock Options. Subject to the provisions of the Plan, the Committee may
grant options to eligible personnel upon such terms and conditions as the
Committee deems appropriate. The terms and conditions of any option shall be
evidenced by a written option agreement or other instrument approved for this
purpose by the Committee.

        (a) Exercise Price. The exercise price per share of Common Stock covered
by an option granted under the Plan may not be less than the fair market value
per share on the date of grant, unless otherwise determined by the Committee
(or, in the case of an ISO granted to an optionee who, at the time the option is
granted, owns stock possessing more than 10% of the total combined voting power
of all classes of stock of the Company or a "subsidiary" of the Company within
the meaning of Section 424 of the Code, 110% of fair market value).



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        (b) Option Term. No option granted under the Plan may be exercisable (if
at all) more than ten years after the date the option is granted (or, in the
case of an ISO granted to a ten percent stockholder described in Section 422 of
the Code, five years).

        (c) Vesting and Exercise of Options. The Committee may establish such
vesting and other conditions and restrictions on the exercise of an option
and/or upon the issuance of Common Stock in connection with the exercise of an
option as it deems appropriate. Subject to satisfaction of applicable
withholding requirements, once vested and exercisable, an option may be
exercised by transmitting to the Company (i) a notice specifying the number of
shares to be purchased and (ii) payment of the exercise price. The exercise
price of an option may be paid in cash and/or such other form of payment as the
Company may permit.

        (d) Rights as a Stockholder. No shares of Common Stock shall be issued
in respect of the exercise of an option until full payment of the exercise price
and the applicable tax withholding obligation with respect to such exercise has
been made or provided for. The holder of an option shall have no rights as a
stockholder with respect to any shares covered by an option until the date such
shares are issued. Except as otherwise provided herein, no adjustments shall be
made for dividend distributions or other rights for which the record date is
prior to the date such shares are issued.

        (e) Buy Out and Settlement. The Committee, on behalf of the Company, may
at any time offer to buy out any outstanding option on such terms and conditions
as the Committee shall establish.

     7. Termination of Employment or Service. Unless otherwise determined by the
Committee at grant or, if no rights of the recipient are thereby reduced,
thereafter, and subject to earlier termination in accordance with the provisions
hereof, the following rules apply with regard to awards held by a recipient at
the time of his or her termination of employment or other service with the
Company.

        (1) Termination by Reason of Death. If a participant's employment or
service terminates by reason of his or her death, then any option held by the
deceased participant shall thereupon become fully vested and may be exercised by
the deceased participant's beneficiary at any time within one year from the date
of death but in no event after expiration of the stated term and, to the extent
not so exercised, will be canceled.

        (2) Termination by Reason of Disability. If a participant's employment
or service is terminated by the Company due to his or her Disability (as
hereinafter defined), then any option held by the participant, to the extent
exercisable on the date his or her employment or service terminates, may be
exercised by the participant at any time within one year from the date his or
her employment or service terminates but in no event after expiration of the
stated term, and, to the extent not so exercised, will be canceled. If the
participant dies during such one-year period, then the deceased participant's
beneficiary may exercise the option, to the extent exercisable by the



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deceased participant immediately prior to his or her death, for a period of one
year following the date of death but in no event after expiration of the stated
term. "Disability" means a participant's absence from employment for at least
180 days in any twelve month period as a result of his or her incapacity due to
physical or mental illness, as determined by the Committee.

        (3) Termination for Cause. If a participant's employment or service is
terminated by the Company for Cause (as hereinafter defined) or if, at the time
of a participant's termination, a ground for termination for Cause exists, then,
notwithstanding anything to the contrary contained herein, any option held by
the participant (whether or not otherwise vested) shall immediately terminate
and cease to be exercisable. "Cause" means (A) in the case where there is no
employment or consulting agreement between the participant and the Company or
where such an agreement exists but does not define "Cause" (or words of like
import), a termination classified by the Company as a termination due to the
participant's dishonesty, fraud, insubordination, willful misconduct, refusal to
perform services or materially unsatisfactory performance of his or her duties,
or (B) in the case where there is an employment or consulting agreement between
the participant and the Company, a termination that is or would be deemed for
"cause" (or words of like import) under such agreement.

        (4) Other Termination. If a participant's employment or service
terminates for any reason (other than death, Disability or Cause or at a time
when Cause exists) or no reason, then any option held by the participant, to the
extent not then exercisable, shall thereupon terminate. Any option held by the
participant which is exercisable at the time of such termination of employment
or service shall remain exercisable during the thirty-day period following such
termination of employment or service or, if sooner, until the expiration of the
stated term of the option and, to the extent not exercised within such period,
shall thereupon terminate.

     8. Fair Market Value. For purposes of the Plan, the fair market value of a
share of Common Stock, as of any date, shall be determined in good faith by the
Board in a uniform and consistent manner.

     9. Non-Transferability. No stock option granted under the Plan shall be
transferable by the recipient other than upon the recipient's death to a
beneficiary designated by the recipient in a manner acceptable to the Committee,
or, if no designated beneficiary shall survive the recipient, pursuant to the
recipient's will or by the laws of descent and distribution. All stock options
shall be exercisable during the recipient's lifetime only by the recipient.
Except as otherwise specifically provided by law, no award received under the
Plan may be transferred in any manner, and any attempt to transfer any such
award shall be void, and no such award shall in any manner be liable for or
subject to the debts, contracts, liabilities, engagements or torts of any person
who shall be entitled to such award, nor shall it be subject to attachment or
legal process for or against such person. Notwithstanding the foregoing, the
Committee may determine at the time of grant or thereafter that an NQSO is
transferable in whole or part to such persons, under such circumstances, and
subject to such conditions as the Committee may prescribe.



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     10. Other Conditions. The Committee may impose such other conditions with
respect to the grant of awards or the issuance of shares of Common Stock
pursuant to the Plan, including, without limitation, conditions relating to the
application of federal or state securities laws or exchange requirements as it
deems necessary or advisable.

     11. Capital Changes; Change in Control; Merger.

        (a) Adjustments Upon Changes in Capitalization. The aggregate number and
class of shares for which awards may be granted under the Plan, the maximum
number of shares that may be covered by individual awards in any year, the
number and class of shares covered by each outstanding award and, if applicable,
the exercise price per share shall all be adjusted proportionately or as
otherwise appropriate to reflect any increase or decrease in the number of
issued shares of Common Stock resulting from a split-up or consolidation of
shares or any like capital adjustment, or the payment of any stock dividend,
and/or to reflect a change in the character or class of shares covered by the
Plan arising from a readjustment or recapitalization of the Company's capital
stock.

        (b) Change in Control. The Committee may provide in any award agreement
for the effect on the award of a "change in control" of the Company or any of
its subsidiaries or affiliates (as such term is defined by the Committee in any
such award agreement), including, without limitation, the acceleration of the
exercisability of, or the lapse of restrictions or deemed satisfaction of goals
with respect to, any outstanding awards.

        (c) Merger; Consolidation. Unless otherwise provided in the applicable
award agreement, in the event of a merger, consolidation, mandatory share
exchange or other similar business combination of the Company with or into any
other entity ("Successor Entity") or any transaction in which another person or
entity acquires all the issued and outstanding Common Stock, or all or
substantially all the assets of the Company, outstanding awards may be assumed
or an equivalent award may be substituted by the Successor Entity or a parent or
subsidiary of the Successor Entity.

        (d) Fractional Shares. In the event of any adjustment in the number of
shares covered by any option pursuant to the provisions hereof, any fractional
shares resulting from such adjustment shall be disregarded, and each such option
shall cover only the number of full shares resulting from the adjustment.

        (e) Determinations Final. All adjustments under this Section 13 shall be
made by the Committee, and its determination as to what adjustments shall be
made, and the extent thereof, shall be final, binding and conclusive.

     12. Tax Withholding. As a condition to the exercise of any award or the
delivery of any shares of Common Stock pursuant to any award or the lapse of
restrictions on any award, or in connection with any other event that gives rise
to a federal or other governmental tax withholding obligation on the part of the
Company relating to an award, (a) the Company may deduct or withhold



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(or cause to be deducted or withheld) from any payment or distribution to a
grantee whether or not pursuant to the Plan or (b) the Company shall be entitled
to require that the grantee remit cash to the Company (through payroll deduction
or otherwise), in each case in an amount sufficient in the opinion of the
Company to satisfy such withholding obligation. If the event giving rise to the
withholding obligation involves a transfer of shares of Common Stock, then,
unless the applicable award agreement provides otherwise, at the discretion of
the Committee, the grantee may satisfy the withholding obligation described
under this Section 14 by electing to have the Company withhold shares of Common
Stock (which withholding will be at a rate not in excess of the statutory
minimum rate) or by tendering previously owned shares of Common Stock, in each
case having a fair market value equal to the amount of tax to be withheld (or by
any other mechanism as may be required or appropriate to conform with local tax
and other rules).

     13. Amendment and Termination. The Board may amend or terminate the Plan,
provided, however, that no such action may affect adversely the accrued rights
of the holder of any outstanding award without the consent of the holder. Except
as otherwise provided in Section 13, any amendment which would increase the
number of shares of Common Stock for which awards may be granted under the Plan
(in the aggregate or on an individual basis) or modify the class of individuals
eligible to receive awards under the Plan shall be subject to the approval of
the Company's stockholders. The Committee may amend the terms of any agreement
or certificate made or issued hereunder at any time and from time to time,
provided, however, that any amendment which would adversely affect the accrued
rights of the holder may not be made without his or her consent.

     14. No Rights Conferred. Nothing contained herein shall be deemed to give
any individual any right to receive an award under the Plan or to be retained in
the employ or service of the Company.

     15. Decisions and Determinations to be Final. All decisions and
determinations made by the Board pursuant to the provisions hereof and, except
to the extent rights or powers under the Plan are reserved specifically to the
discretion of the Board, all decisions and determinations of the Committee shall
be final, binding and conclusive.

     16. Governing Law. All rights and obligations under the Plan and each award
agreement or instrument shall be governed by and construed in accordance with
the laws of the State of Delaware, without regard to its principles of conflict
of laws.

     17. Term of the Plan. The Plan shall become effective on the date of its
adoption by the Board. Unless sooner terminated by the Board, the Plan shall
terminate on the tenth anniversary of the date of its adoption by the Board. The
rights of any person with respect to an award made under the Plan that is
outstanding at the time of the termination of the Plan shall not be affected
solely by reason of the termination of the Plan and shall continue in accordance
with the terms of the award (as then in effect or thereafter amended) and the
Plan.