TUMBLEWEED COMMUNICATIONS CORP.

2000 NSO INCENTIVE STOCK PLAN

(as amended and restated as of March 4, 2001)

Section 1. General Purpose of Plan; Definitions.

The name of this plan is the Tumbleweed Communications Corp. 2000 NSO Incentive Stock Plan (the "Plan"). The Plan was adopted by the Board (defined below) on
July 10, 2000 (the "Effective Date") and was amended by the Board to increase the number of shares reserved for issuance under the Plan on October 17, 2000 and on November 20,
2000 and on March 4, 2001. The purpose of the Plan is to enable the Company to attract and retain highly qualified personnel who will contribute to the Company's success and to provide
incentives to Participants (defined below) that are linked directly to increases in stockholder value and will therefore inure to the benefit of all stockholders of the Company. This Plan is intended
to qualify as a "broadly based" plan for purposes of the shareholder approval rules promulgated by the NASD (defined below).

For
purposes of the Plan, the following terms shall be defined as set forth below:

(1) "Administrator" means the Board, or if and to the extent the Board does not administer the Plan, the Committee in
accordance with Section 2 below.

(2) "Board" means the Board of Directors of the Company.

(3) "Code" means the Internal Revenue Code of 1986, as amended from time to time, or any successor thereto.

(4) "Committee" means any committee the Board may appoint to administer the Plan. To the extent necessary and desirable,
the Committee shall be composed entirely of individuals who meet the qualifications referred to in Rule 16b-3 under the Exchange Act. If at any time or to any extent the Board shall
not administer the Plan, then the functions of the Board specified in the Plan shall be exercised by the Committee.

(5) "Company" means Tumbleweed Communications Corp., a Delaware corporation (or any successor corporation).

(6) "Deferred Stock" means the right to receive Stock at the end of a specified deferral period granted pursuant to
Section 7 below.

(7) "Disability" means the inability of a Participant to perform substantially his or her duties and responsibilities to
the Company or to any Parent or Subsidiary by reason of a physical or mental disability or infirmity (i) for a continuous period of six months, or (ii) at such earlier time as the
Participant submits medical evidence satisfactory to the Administrator that the Participant has a physical or mental disability or infirmity that will likely prevent the Participant from returning to
the performance of the Participant's work duties for six months or longer. The date of such Disability shall be the last day of such six-month period or the day on which the Participant
submits such satisfactory medical evidence, as the case may be.

(8) "Eligible Recipient" means (i) an employee, consultant or advisor of the Company or of any Parent or
Subsidiary (other than any officer or director of the Company or of any Parent or Subsidiary) or (ii) an individual who becomes an officer or director of the Company or of any Parent or
Subsidiary following the Effective Date.

(9) "Exchange Act" means the Securities Exchange Act of 1934, as amended from time to time.

(10) "Fair Market Value" means, as of any given date, with respect to any awards granted hereunder, (A) if the
Stock is publicly traded, the closing sale price of a share of Stock, (B) the fair market value of a share of Stock as determined in accordance with a method prescribed in the agreement
evidencing any award hereunder or (C) the fair market value of a share of Stock as otherwise determined by the Administrator in the good faith exercise of its discretion.

(11) "NASD" means the National Association of Securities Dealers, Inc.

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(12) "Parent" means any corporation (other than the Company) in an unbroken chain of corporations ending with the
Company, if each of the corporations in the chain (other than the Company) owns stock possessing 50% or more of the combined voting power of all classes of stock in one of the other corporations in
the chain.

(13) "Participant" means any Eligible Recipient selected by the Administrator, pursuant to the Administrator's authority
in Section 2 below, to receive grants of Stock Options, Stock Appreciation Rights, awards of Restricted Stock, Deferred Stock, or Performance Shares or any combination of the foregoing.

(14) "Performance Shares" means shares of Stock that are subject to restrictions based upon the attainment of specified
performance objectives granted pursuant to Section 7 below.

(15) "Restricted Stock" means shares of Stock subject to certain restrictions granted pursuant to Section 7
below.

(16) "Stock" means the common stock, par value $0.001 per share, of the Company.

(17) "Stock Appreciation Right" means the right pursuant to an award granted under Section 6 below to receive an
amount equal to the excess, if any, of (A) the Fair Market Value, as of the date such Stock Appreciation Right or portion thereof is surrendered, of the shares of Stock covered by such right or
such portion thereof, over (B) the aggregate exercise price of such right or such portion thereof.

(18) "Stock Option" means an option to purchase shares of Stock granted pursuant to Section 5.

(19) "Subsidiary" means any corporation (other than the Company) in an unbroken chain of corporations beginning with the
Company, if each of the corporations (other than the last corporation) in the unbroken chain owns stock possessing 50% or more of the total combined voting power of all classes of stock in one of the
other corporations in the chain.

Section 2. Administration.

To the extent necessary and desirable, the Plan shall be administered in accordance with the requirements of Rule 16b-3 under the Exchange
Act ("Rule 16b-3") by the Board or, at the Board's sole discretion, by the Committee, which shall be appointed by the Board, and which shall serve at the pleasure of the Board.

Pursuant
to the terms of the Plan, the Administrator shall have the power and authority to grant to Eligible Recipients pursuant to the terms of the Plan: (a) Stock Options,
(b) Stock Appreciation Rights, (c) awards of Restricted Stock, Deferred Stock or Performance Shares or (d) any combination of the foregoing. In particular, the Administrator shall
have the authority:



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The
Administrator shall have the authority, in its sole discretion, to adopt, alter and repeal such administrative rules, guidelines and practices governing the Plan as it shall from
time to time deem advisable; to interpret the terms and provisions of the Plan and any award issued under the Plan (and any agreements relating thereto); and to otherwise supervise the administration
of the Plan.

All
decisions made by the Administrator pursuant to the provisions of the Plan shall be final, conclusive and binding on all persons, including, but not limited to the Company and the
Participants.

Section 3. Stock Subject to Plan.

The total number of shares of Stock reserved and available for issuance under the Plan shall be 4,181,500 shares. Such shares may consist, in whole or in part,
of authorized and unissued shares or treasury shares. To the extent that (i) a Stock Option expires or is otherwise terminated without being exercised, or (ii) any shares of Stock
subject to any award of Restricted Stock, Deferred Stock or Performance Shares granted hereunder are forfeited, such shares of Stock shall again be available for issuance in connection with future
awards granted under the Plan. If any shares of Stock have been pledged as collateral for indebtedness incurred by a Participant in connection with the exercise of a Stock Option and such shares of
Stock are returned to the Company in satisfaction of such indebtedness, such shares of Stock shall again be available for issuance in connection with future awards granted under the Plan.

In
the event of any merger, reorganization, consolidation, recapitalization, stock dividend or other change in corporate structure affecting the Stock, an equitable substitution or
proportionate adjustment shall be made in (i) the aggregate number of shares of Stock reserved for issuance under the Plan, (ii) the kind, number and option price of shares of Stock
subject to outstanding Stock Options granted under the Plan, and (iii) the kind, number and purchase price of shares of Stock subject to outstanding awards of Restricted Stock, Deferred Stock
and Performance Shares granted under the Plan, in each case as may be determined by the Administrator, in its sole discretion. Such other substitutions or adjustments shall be made as may be
determined by the Administrator, in its sole discretion. An adjusted option price shall also be used to determine the amount payable by the Company upon the exercise of any Stock Appreciation Right
related to any Stock Option. In connection with any event described in this paragraph, the Administrator may provide, in its sole discretion, for the cancellation of any outstanding awards and payment
in cash or other property therefor.

Section 4. Eligibility.

Eligible Recipients shall be eligible to be granted Stock Options, Stock Appreciation Rights, awards of Restricted Stock, Deferred Stock or Performance Shares
or any combination of the foregoing hereunder. The Participants under the Plan shall be selected from time to time by the Administrator, in its sole discretion, from among the Eligible Recipients, and
the Administrator shall determine, in its sole discretion, the number of shares of Stock covered by each such award.

Section 5. Stock Options.

Stock Options may be granted alone or in addition to other awards granted under the Plan. Any Stock Option granted under the Plan shall be in such form as the
Administrator may from time to time approve, and the provisions of Stock Option awards need not be the same with respect to each Participant. Participants who are granted Stock Options shall enter
into a subscription and/or award agreement with the Company, in such form as the Administrator shall determine, which agreement

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shall set forth, among other things, the option price of the Stock Option, the term of the Stock Option and provisions regarding exercisability of the Stock Option granted thereunder.

The
Stock Options granted under the Plan are not intended to qualify as "incentive stock options" within the meaning of Section 422 of the Code.

The
Administrator shall have the authority to grant to any officer or employee of the Company or of any Parent or Subsidiary (including directors who are also officers of the Company)
Stock Options (with or without Stock Appreciation Rights). More than one Stock Option may be granted to the same Participant and be outstanding concurrently hereunder.

Stock
Options granted under the Plan shall be subject to the following terms and conditions and shall contain such additional terms and conditions, not inconsistent with the terms of
the Plan, as the Administrator shall deem desirable:

(1)Option Price. The option price per share of Stock purchasable under a Stock Option shall be determined by the
Administrator in its sole discretion at the time of grant but shall not be less than the par value of the Stock on such date.

(2)Option Term. The term of each Stock Option shall be fixed by the Administrator.

(3)Exercisability. Stock Options shall be exercisable at such time or times and subject to such terms and conditions as
shall be determined by the Administrator at or after the time of grant. The Administrator may provide at the time of grant, in its sole discretion, that any Stock Option shall be exercisable only in
installments, and the Administrator may waive such installment exercise provisions at any time, in whole or in part, based on such factors as the Administrator may determine, in its sole discretion,
including but not limited to in connection with any change of control.

(4)Method of Exercise. Subject to paragraph (3) of this Section 5, Stock Options may be exercised in
whole or in part at any time during the option period, by giving written notice of exercise to the Company specifying the number of shares of Stock to be purchased, accompanied by payment in full of
the purchase price in cash or its equivalent, as determined by the Administrator. As determined by the Administrator, in its sole discretion, payment in whole or in part may also be made (i) by
means of any cashless exercise procedure approved by the Administrator, (ii) in the form of unrestricted Stock already owned by the Participant which, (x) in the case of unrestricted
Stock acquired upon exercise of an option, have been owned by the Participant for more than six months on the date of surrender, and (y) has a Fair Market Value on the date of surrender equal
to the aggregate option price of the Stock as to which such Stock Option shall be exercised, or (iii) in the case of the exercise of a Stock Option, in the form of Restricted Stock or
Performance Shares subject to an award hereunder (based, in each case, on the Fair Market Value of the Stock on the date the Stock Option is exercised). If payment of the option price of a Stock
Option is made in whole or in part in the form of Restricted Stock or Performance Shares, the shares of Stock received upon the exercise of such Stock Option shall be restricted in accordance with the
original terms of the Restricted Stock award or Performance Shares award in question, except that the Administrator may direct that such restrictions shall apply only to that number of shares of Stock
equal to the number of shares surrendered upon the exercise of such Stock Option. A Participant shall generally have the rights to dividends and any other rights of a stockholder with respect to the
Stock subject to the Stock Option only after the Participant has given written notice of exercise, has paid in full for such shares, and, if requested, has given the representation described in
paragraph (2) of Section 10 below.

The
Administrator may require the surrender of all or a portion of any Stock Option granted under the Plan as a condition precedent to the grant of a new Stock Option. Subject to the
provisions of the Plan, such new Stock Option shall be exercisable at the price, during such period and on such other terms and conditions as are specified by the Administrator at the time the new
Stock Option is granted. Upon their surrender, Stock Options shall be canceled and the shares of Stock previously

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subject to such canceled Stock Options shall again be available for future grants of Stock Options and other awards hereunder.

(5)Loans. The Company or any Parent or Subsidiary may make loans available to Stock Option holders in connection with
the exercise of outstanding Stock Options, as the Administrator, in its sole discretion, may determine. Such loans shall (i) be evidenced by promissory notes entered into by the Stock Option
holders in favor of the Company or any Parent or Subsidiary, (ii) be subject to the terms and conditions set forth in this Section 5(5) and such other terms and conditions, not
inconsistent with the Plan, as the Administrator shall determine, (iii) bear interest at the applicable Federal interest rate or such other rate as the Administrator shall determine, and
(iv) be subject to Board approval (or to approval by the Administrator to the extent the Board may delegate such authority). In no event may the principal amount of any such loan exceed the sum
of (x) the aggregate option price less the par value (if any) of the shares of Stock covered by the Stock Option, or portion thereof, exercised by the holder, and (y) any Federal, state,
and local income tax attributable to such exercise. The initial term of the loan, the schedule of payments of principal and interest under the loan, the extent to which the loan is to be with or
without recourse against the holder with respect to principal and/or interest and the conditions upon which the loan will become payable in the event of the holder's termination of service to the
Company or to any Parent or Subsidiary shall be determined by the Administrator. Unless the Administrator determines otherwise, when a loan is made, shares of Stock having a Fair Market Value at least
equal to the principal amount of the loan shall be pledged by the holder to the Company as security for payment of the unpaid balance of the loan, and such pledge shall be evidenced by a pledge
agreement, the terms of which shall be determined by the Administrator, in its sole discretion;provided, however, that each loan shall comply with all
applicable laws, regulations and rules of the Board of Governors of the Federal Reserve System and any other governmental agency having jurisdiction.

(6)Non-Transferability of Stock Options. Except under the laws of descent and distribution, unless
otherwise determined by the Administrator, the optionee shall not be permitted to sell, transfer, pledge or assign any Stock Option, and all Stock Options shall be exercisable, during the optionee's
lifetime, only by the optionee;provided, however, that the optionee shall be permitted to transfer one or more Stock Options to a trust controlled by
the optionee during the optionee's lifetime for estate planning purposes.

(7)Termination of Employment or Service. If a Participant's employment with or service as a director, consultant or
advisor to the Company or to any Parent or Subsidiary terminates by reason of his or her death, Disability or for any other reason, the Stock Option may thereafter be exercised to the extent provided
in the agreement evidencing such Stock Option, or as otherwise determined by the Administrator following termination of employment.

Section 6. Stock Appreciation Rights.

Stock Appreciation Rights may be granted either alone ("Free Standing Rights") or in conjunction with all or part of any Stock Option granted under the Plan
("Related Rights"). Related Rights may be granted either at or after the time of the grant of the Stock Option. The Administrator shall determine the Eligible Recipients to whom, and the time or times
at which, grants of Stock Appreciation Rights shall be made; the number of shares of Stock to be awarded, the exercise price, and all other conditions of Stock Appreciation Rights. The provisions of
Stock Appreciation Rights need not be the same with respect to each Participant.

Stock
Appreciation Rights granted under the Plan shall be subject to the following terms and conditions and shall contain such additional terms and conditions, not inconsistent with
the terms of the Plan, as the Administrator shall deem desirable:

(1)Awards. The prospective recipient of a Stock Appreciation Right shall not have any rights with respect to such
award, unless and until such recipient has executed an agreement evidencing the award

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(a "Stock Appreciation Right Agreement") and delivered a fully executed copy thereof to the Company, within a period of sixty days (or such other period as the Administrator may specify) after the
award date. Participants who are granted Stock Appreciation Rights shall have no rights as stockholders of the Company with respect to the grant or exercise of such rights.

(2)Exercisability.



(3)Payment Upon Exercise.



(4)Non-Transferability.



(5)Termination of Employment or Service.



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(6)Term.



Section 7. Restricted Stock, Deferred Stock and Performance Shares.

Awards of Restricted Stock, Deferred Stock or Performance Shares may be issued either alone or in addition to other awards granted under the Plan. The
Administrator shall determine the Eligible Recipients to whom, and the time or times at which, awards of Restricted Stock, Deferred Stock or Performance Shares shall be made; the number of shares to
be awarded; the price, if any, to be paid by the Participant for the acquisition of Restricted Stock, Deferred Stock or Performance Shares; the Restricted Period (as defined in paragraph (2) of
this Section 7) applicable to awards of Restricted Stock or Deferred Stock; the performance objectives applicable to awards of Deferred Stock or Performance Shares; and all other conditions of
the awards of Restricted Stock, Deferred Stock and Performance Shares. The Administrator may also condition the grant of the award of Restricted Stock, Deferred Stock or Performance Shares upon the
exercise of Stock Options, or upon such other criteria as the Administrator may determine, in its sole discretion. The provisions of the awards of Restricted Stock, Deferred Stock or Performance
Shares need not be the same with respect to each Participant. In the sole discretion of the Administrator, loans may be made to Participants in connection with the purchase of Restricted Stock under
substantially the same terms and conditions as provided in paragraph (5) of Section 5 of the Plan with respect to the exercise of Stock Options.

(1)Awards and Certificates. The prospective recipient of awards of Restricted Stock, Deferred Stock or Performance
Shares shall not have any rights with respect to any such award, unless and until such recipient has executed an agreement evidencing the award (a "Restricted Stock Award Agreement," "Deferred Stock
Award Agreement" or "Performance Shares Award Agreement," as appropriate) and delivered a fully executed copy thereof to the Company, within a period of sixty days (or such other period as the
Administrator may specify) after the award date. Except as otherwise provided below in this Section 7(2), (i) each Participant who is granted an award of Restricted Stock or Performance
Shares shall be issued a stock certificate in respect of such shares of Restricted Stock or Performance Shares; and (ii) such certificate shall be registered in the name of the Participant, and
shall bear an appropriate legend referring to the terms, conditions, and restrictions applicable to any such award.

The
Company may require that the stock certificates evidencing Restricted Stock or Performance Shares granted hereunder be held in the custody of the Company until the restrictions
thereon shall have lapsed, and that, as a condition of any award of Restricted Stock or Performance Shares, the Participant shall have delivered a stock power, endorsed in blank, relating to the Stock
covered by such award.

With
respect to awards of Deferred Stock, at the expiration of the Restricted Period, stock certificates in respect of such shares of Deferred Stock shall be delivered to the
Participant, or his legal representative, in a number equal to the number of shares of Stock covered by the Deferred Stock award.

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(2)Restrictions and Conditions. The awards of Restricted Stock, Deferred Stock and Performance Shares granted pursuant
to this Section 7 shall be subject to the following restrictions and conditions:



Section 8. Amendment and Termination.

The Board may amend, alter or discontinue the Plan, but no amendment, alteration, or discontinuation shall be made that would impair the rights of a
Participant under any award theretofore granted without such Participant's consent.

The
Administrator may amend the terms of any award theretofore granted, prospectively or retroactively, but, subject to Section 3 of Plan, no such amendment shall impair the
rights of any Participant without his or her consent.

Section 9. Unfunded Status of Plan.

The Plan is intended to constitute an "unfunded" plan for incentive compensation. With respect to any payments not yet made to a Participant by the Company,
nothing contained herein shall give any such Participant any rights that are greater than those of a general creditor of the Company.

Section 10. General Provisions.

(1) Shares
of Stock shall not be issued pursuant to the exercise of any award granted hereunder unless the exercise of such award and the issuance and delivery of such
shares of Stock pursuant thereto shall comply with all relevant provisions of law, including, without limitation, the Securities Act of 1933, as amended, the Exchange Act and the requirements of any
stock exchange upon which the

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Stock may then be listed, and shall be further subject to the approval of counsel for the Company with respect to such compliance.

(2) The
Administrator may require each person acquiring shares of Stock hereunder to represent to and agree with the Company in writing that such person is acquiring
the shares of Stock without a view to distribution thereof. The certificates for such shares of Stock may include any legend which the Administrator deems appropriate to reflect any restrictions on
transfer.

All
certificates for shares of Stock delivered under the Plan shall be subject to such stock-transfer orders and other restrictions as the Administrator may deem advisable under the
rules, regulations, and other requirements of the Securities and Exchange Commission, any stock exchange upon which the Stock is then listed, and any applicable Federal or state securities law, and
the Administrator may cause a legend or legends to be placed on any such certificates to make appropriate reference to such restrictions.

(3) Nothing
contained in the Plan shall prevent the Board from adopting other or additional compensation arrangements, subject to stockholder approval, if such approval
is required; and such arrangements may be either generally applicable or applicable only in specific cases. The adoption of the Plan shall not confer upon any Eligible Recipient any right to continued
employment or service with the Company or any Parent or Subsidiary, as the case may be, nor shall it interfere in any way with the right of the Company or any Parent or Subsidiary to terminate the
employment or service of any of its Eligible Recipients at any time.

(4) Each
Participant shall, no later than the date as of which the value of an award first becomes includible in the gross income of the Participant for Federal income
tax purposes, pay to the Company, or make arrangements satisfactory to the Administrator regarding payment of, any Federal, state, or local taxes of any kind required by law to be withheld with
respect to such award. The obligations of the Company under the Plan shall be conditional on the making of such payments or arrangements, and the Company shall, to the extent permitted by law, have
the right to deduct any such taxes from any payment of any kind otherwise due to the Participant.

(5) No
member of the Board or the Administrator, nor any officer or employee of the Company acting on behalf of the Board or the Administrator, shall be personally
liable for any action, determination, or interpretation taken or made in good faith with respect to the Plan, and all members of the Board or the Administrator and each and any officer or employee of
the Company acting on their behalf shall, to the extent permitted by law, be fully indemnified and protected by the Company in respect of any such action, determination or interpretation.

Section 11. Term of Plan.

No Stock Option, Stock Appreciation Right, or award of Restricted Stock, Deferred Stock or Performance Shares shall be granted pursuant to the Plan on or after
the tenth anniversary of the Effective Date, but awards theretofore granted may extend beyond that date.

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