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                                                                     Exhibit 4.2











                             PRICEINTERACTIVE, INC.

                              AMENDED AND RESTATED

                           2000 RESTRICTED STOCK PLAN

                     (AS AMENDED THROUGH FEBRUARY __, 2001)



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                                TABLE OF CONTENTS


<TABLE>
<S>                                                                                         <C>

1.  Purpose.....................................................................................1

2.  Definitions.................................................................................1

3.  Term of thePlan.............................................................................4

4.  Stock Subject to the Plan...................................................................4

5.  Administration..............................................................................4

6.  Authorization and Eligibility...............................................................5

7.  Expiration of Awards........................................................................5

8.  Fractional Shares...........................................................................6

9.  Settlement of Awards........................................................................6

10. Unfunded Status of Plan.....................................................................8

11. Non-Transferability of Awards...............................................................8

12. No Special Employment or Other Rights.......................................................9

13. Nonexclusivity of the Plan..................................................................9

14. Termination and Amendment of the Plan.......................................................9

15. Reservation of Stock........................................................................9

16. Governing Law...............................................................................10
</TABLE>


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                             PRICEINTERACTIVE, INC.

                              AMENDED AND RESTATED

                           2000 RESTRICTED STOCK PLAN

                     (AS AMENDED THROUGH FEBRUARY __, 2001)


1. PURPOSE

         This Plan is the "Restricted Stock Plan" contemplated by Sections
10.4(b) and 10.20 of the Agreement and Plan of Merger and Reorganization, dated
as of December 12, 2000 (the "MERGER AGREEMENT"), by and among iBasis, Inc., a
Delaware corporation ("IBASIS"), Penguin Acquisition Corp., a Delaware
corporation and a wholly-owned subsidiary of iBasis ( "MERGER SUB"),
PriceInteractive, Inc. (the "COMPANY"), and the Principal Company Stockholders
and the Stockholder Representatives named therein, pursuant to which iBasis will
acquire all of the issued and outstanding capital stock of the Company through
the merger of the Company with and into Merger Sub (the "MERGER"), with Merger
Sub being the surviving corporation in the Merger (the "SURVIVING CORPORATION").

         This Plan is intended to encourage retention of the Company employees
and to provide additional incentive for them to promote the success of the
business of the Company, iBasis and the Surviving Corporation. This Plan shall
at all times be administered and operated in accordance with the Merger
Agreement applicable thereto and the terms set forth herein. This Plan and the
Awards made hereunder will be effective immediately prior to, and contingent
upon, the Effective Time. Awards made under the Plan shall be conditioned on the
Participant agreeing to certain terms consistent with the Merger Agreement, as
determined by the Board of Directors prior to the Effective Time when making
Awards. Pursuant to the Merger Agreement, iBasis will assume this Plan in
connection with the Merger. This Plan and the initial Awards made hereunder
prior to the Effective Time have been approved by the holders of more than 75%
of the voting power of the outstanding capital stock of the Company.

2. DEFINITIONS

         As used in this Plan, the following terms shall have the following
meanings:

         2.1. AFFILIATE means a corporation or other entity controlled by,
controlling or under common control with the Company.

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                                      -2-


         2.2. AWARD means an award made hereunder of restricted Common Stock
vesting upon and only to the extent provided in the Vesting Conditions.

         2.3. AWARD AGREEMENT means an agreement between the Company and a
Participant pursuant to which an Award is made.

         2.4. BOARD means, until the Effective Time, the Board of Directors of
the Company; and after the Effective Time, the Board of Directors of iBasis.

         2.5. CAUSE means (a) actions materially detrimental to the interests of
the Surviving Corporation or iBasis or (b) willful neglect of responsibilities
to the Surviving Corporation or iBasis, in each case continuing following
written notice from the Surviving Corporation or iBasis to the effect that Cause
exists.

         2.6. CODE means the Internal Revenue Code of 1986, as amended from time
to time.

         2.7. COMMITTEE means Daniel J. Price or, if he is unable to act for any
reason, Timothy M. Price or, if he is unable to act for any reason, Daniel E.
Moore.

         2.8. COMMON STOCK or STOCK means, prior to the Effective Time, the
Class A common stock, $0.01 par value per share, of the Company and, after the
Effective Time, the shares of common stock, $0.001 par value per share, of
iBasis into which the common stock of the Company issued pursuant to Awards
hereunder are converted pursuant to the terms of the Merger Agreement.

         2.9. COMPANY means, until the Effective Time, the Company, and its
successors, and after the Effective Time, iBasis and its successors.

         2.10. EFFECTIVE TIME means the Effective Time (as defined in the Merger
Agreement).

         2.11. FAIR MARKET VALUE means (i) the closing sale price for shares of
Common Stock on the Nasdaq Stock Market or other principal exchange or market on
which or in which the Common Stock is traded for the most recent trading day
prior to the date on which such determination is made and (ii) if the Common
Stock is not traded on a stock exchange or on the Nasdaq National Market, the
value of a share of Common Stock on such date as determined by the Committee.

         2.12. PARTICIPANT means any holder of an outstanding Award under the
Plan.


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                                      -3-


         2.13. PLAN means this Amended and Restated 2000 Restricted Stock Plan,
as further amended from time to time.

         2.14. RESTRICTED SHARES means any shares of Common Stock issued
pursuant to an Award and subject to the Vesting Conditions thereof.

         2.15. SELECT EMPLOYEES means those employees of the Company listed on
Exhibit A hereto who (i) were issued stock options by the Company prior to
January 1, 2000, (ii) have, pursuant to a written document approved by the
Company, waived their rights to accelerated vesting of the number of options set
forth on Exhibit A in the event of a change in control, and (iii) have executed
and delivered employment and related agreements required by the Merger
Agreement.

         2.16. VESTING CONDITIONS means the condition that a Participant will be
entitled to the Restricted Shares subject to an Award, if ever, only if the
Participant is an employee of the Surviving Corporation or iBasis on the
applicable Vesting Date and has been such an employee of the Surviving
Corporation or iBasis continuously from the Effective Time to such date;
PROVIDED that if:

         (a)      a Select Employee ceases to be such an employee for any reason
                  other than voluntary resignation by the Select Employee,

                  (i)      prior to January 1, 2002, such Select Employee shall
                           be deemed to have satisfied the Vesting Conditions as
                           to the greatest of (x) 50% of the Restricted Shares
                           subject to the Select Employee's Award(s), (y) a
                           number of Restricted Shares equal to the product of
                           (A) the number of Company stock options listed on
                           Exhibit A as to which change of control vesting was
                           waived prior to the Effective Time and (B) the Common
                           Stock Exchange Ratio (as defined in the Merger
                           Agreement) or (z) such number of Restricted Shares as
                           to which the Committee shall determine in its sole
                           discretion that the Vesting Conditions shall be
                           deemed to have been satisfied; and

                  (ii)     following April 1, 2002, such Select Employee shall
                           be deemed to have satisfied the Vesting Conditions as
                           to 100% of the Restricted Shares subject to the
                           Select Employee's Award(s).

         (b)      a Participant who is not a Select Employee ceases to be an
                  employee (i) on or before January 1, 2002 by reason of
                  termination by the Surviving Corporation or iBasis without
                  Cause, or (ii) before

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                                      -4-


                  January 1, 2003 only if specifically approved by the Committee
                  in its sole discretion, such Participant shall be deemed to
                  have satisfied the Vesting Conditions as to the Restricted
                  Shares that would vest on the next applicable Vesting Date,
                  unless the Committee determines in its sole discretion that
                  vesting of additional Restricted Shares is appropriate.

         2.17. VESTING DATE means, with respect to one-half of the Restricted
Shares subject to each Award, January 1, 2002, and, with respect to the other
half of such Restricted Shares, January 1, 2003.

3. TERM OF THE PLAN

         Awards will be granted under this Plan only in the period commencing as
of the effective date of this Plan and ending at the Effective Time. Pursuant to
Section 4 hereof, the Committee may make Awards of additional Restricted Shares
to persons selected by the Committee to replace shares that are forfeited by
Participants for any reason at any time prior to January 1, 2003.

4. STOCK SUBJECT TO THE PLAN

         At no time shall the number of shares of Common Stock issued pursuant
to or subject to outstanding Awards granted under the Plan exceed two million
seven hundred fifty thousand (2,750,000) shares of Common Stock prior to the
Effective Time, or the product of two million seven hundred fifty thousand
(2,750,000) multiplied by the Common Stock Exchange Ratio (as defined in the
Merger Agreement) after the Effective Time. Shares of Common Stock issued
pursuant to the Plan may be either authorized but unissued shares or shares held
by the Company in its treasury. In the event that at any time and from time to
time any shares of Common Stock subject to Awards are forfeited, the Committee
may grant additional Awards of up to a number of shares of Common Stock equal to
the number of forfeited shares to other Participants or other employees of the
Company or the Surviving Corporation as determined by the Committee in its sole
discretion.

5. ADMINISTRATION

         The Plan shall be administered by the Committee. Subject to the
provisions of the Plan, the Committee shall have complete authority, in its
discretion, to make or to select the manner of making all determinations with
respect to each initial Award to be granted by the Company under the Plan and
each additional Award granted with respect to forfeited Restricted Shares,
including the employee to receive the Award and whether and to what extent the
Vesting Conditions shall be deemed to have been satisfied as


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                                      -5-


to additional Restricted Shares as contemplated by Section 2.16. In making such
determinations, the Committee may take into account the nature of the services
rendered by the employees, their present and potential contributions to the
success of the Company and its subsidiaries, and such other factors as the
Committee in its discretion shall deem relevant. Subject to the provisions of
the Plan and Award Agreements, the Committee shall also have complete authority
to interpret the Plan, to prescribe, amend and rescind rules and regulations
relating to it, to determine the terms and provisions of the respective Awards
(which need not be identical), and to make all other determinations necessary or
advisable for the administration of the Plan. The Committee's determinations
made in good faith on matters referred to in this Plan shall be final, binding
and conclusive on the Company and on all persons having or claiming any interest
under this Plan or an Award made pursuant to hereto.

6. AUTHORIZATION AND ELIGIBILITY

         Immediately prior to the Effective Time, the Committee shall grant,
subject to the consummation of the Merger and the occurrence of the Effective
Time, the Awards described on EXHIBIT A attached hereto. Each grant of an Award,
whether prior to or following the Effective Time, shall be subject to all
applicable terms and conditions of the Plan, including the Vesting Conditions,
and such other terms and conditions, not inconsistent with the terms of the
Plan, as the Committee may prescribe, and shall be evidenced by an Award
Agreement or other document delivered to the Participant and in such form as the
Committee may specify.

7. EXPIRATION OF AWARDS

         Each Award shall be forfeited, to the extent the Vesting Conditions
applicable thereto have not been satisfied, immediately following the Vesting
Date or, if earlier, on termination of the Participant's employment if, and only
if, such termination constitutes failure of the Vesting Conditions. None of
iBasis, the Company or the Surviving Corporation shall have any liability or
obligation in respect of forfeited Awards, and, immediately upon such
forfeiture, all shares of Common Stock subject to forfeited Awards shall,
without further action, be cancelled, and shall no longer be treated as
outstanding shares of Common Stock for any purpose.

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                                      -6-


8. FRACTIONAL SHARES

         No fraction of a share shall be deliverable upon settlement of an
Award, but in the event any adjustment hereunder of the number of shares covered
by an Award shall cause such number to include a fraction of a share, such
number of shares shall be adjusted to the nearest smaller whole number of
shares, with fractional shares to be paid in cash based on the Fair Market Value
of a share of Common Stock on the date of payment.

9. SETTLEMENT OF AWARDS

         9.1. DELIVERY OF STOCK. Upon satisfaction of the Vesting Conditions
applicable to an Award, the Company shall deliver to the Participant holding
such Award, or if the Participant has died, to the Participant's designated
beneficiary (or, if none, the Participant's estate), the certificate
representing the shares of Common Stock described therein. Shares subject to
such certificate shall be transferred for no cash consideration. The Company
shall file, as soon as practicable after the Effective Time, a registration
statement on Form S-8 (or other appropriate form) under the Securities Act (as
defined in the Merger Agreement) to register the shares of Common Stock issued
or issuable under the Plan, and shall cause such registration statement to
remain effective until the delivery of all shares under the Plan.

         9.2. VIOLATION OF LAW. Notwithstanding any other provision of the Plan,
if, at any time, in the reasonable opinion of the Company, the issuance of
shares of Common Stock covered by an Award may constitute a violation of law,
then the Company may delay such issuance and the delivery of a certificate for
such shares until (i) approval shall have been obtained from such governmental
agencies, other than the Securities and Exchange Commission, as may be required
under any applicable law, rule, or regulation and (ii) in the case where such
issuance would constitute a violation of a law administered by or a regulation
of the Securities and Exchange Commission, one of the following conditions shall
have been satisfied:

             (a) the shares are at the time of the issue of such shares
effectively registered under the Securities Act of 1933, as amended; or

             (b) the Company shall have determined, on such basis as it deems
appropriate (including an opinion of counsel in form and substance satisfactory
to the Company), that the sale, transfer, assignment, pledge, encumbrance or
other disposition of such shares or such beneficial interest, as the case may
be, does not require registration under the Securities Act of 1933, as amended
or any applicable State securities laws.

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The Company shall use its reasonable best efforts to bring about the occurrence
of said events.

         9.3. TAX WITHHOLDING. Whenever shares of Common Stock are issued or to
be issued pursuant to Awards granted under the Plan, or the Vesting Conditions
with respect to such Restricted Shares are satisfied in whole or in part, the
Company shall have the right to require the recipient to remit to the Company an
amount sufficient to satisfy federal, state, local or other withholding tax
requirements if, when, and to the extent required by law (whether so required to
secure for the Company an otherwise available tax deduction or otherwise) prior
to the delivery of any certificate or certificates for such shares. The
obligations of the Company under the Plan shall be conditional on satisfaction
of all such withholding obligations 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 recipient of an Award. In the sole discretion of
the Board of Directors of iBasis, the Participant may be permitted to satisfy
any such withholding by surrendering shares of Common Stock otherwise receivable
under the Plan, based on the Fair Market Value of a share of Common Stock on the
date on which the withholding is made, PROVIDED the amount so withheld does not
exceed the minimum withholding allowed.

         If Participants are not permitted to satisfy withholding obligations by
the surrender of shares otherwise receivable under the Plan, the Company shall
provide that payment of the withholding taxes may in full or in part be made by
delivering a notice to the Company, together with a copy of irrevocable
instructions to a broker to deliver promptly to the Company the amount of sale
proceeds necessary to pay the amount of any federal, state, local or foreign
withholding taxes. To facilitate the foregoing, the Company shall enter into
agreements for coordinated procedures with one or more brokerage firms.

         9.4. RIGHTS PENDING ISSUANCE. Subject to Section 11 of the Plan, the
Participant shall have, with respect to the shares of Common Stock underlying an
Award, the rights of a stockholder of the Company holding the class or series of
Common Stock that is the subject of the Award, including, if applicable, the
right to vote the shares, and the right to receive any cash dividends, provided
that cash dividends on the class or series of Common Stock that is the subject
of the Award shall be automatically deferred and held by the Company on behalf
of the Participant subject to the vesting of the underlying Award and shall be
payable in cash upon, but only upon, the vesting of the underlying Award.


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         9.5. AWARDS AND CERTIFICATES. Awards shall be evidenced in such manner
as the Committee may deem appropriate, including book-entry registration or
issuance of one or more stock certificates. Any certificate issued in respect of
Restricted Shares prior to the satisfaction of the Vesting Conditions with
respect to such Restricted Shares shall be registered in the name of such
Participant and shall bear an appropriate legend referring to the terms,
conditions, and restrictions applicable to such Award, substantially in the
following form:

                  "The transferability of this certificate and the shares of
                  stock represented hereby are subject to the terms and
                  conditions (including forfeiture) of the PriceInteractive,
                  Inc. Amended and Restated 2000 Restricted Stock Plan and the
                  applicable Award Agreement thereunder, as each has been
                  assumed by iBasis. Copies of such Plan and Agreement are on
                  file at the offices of iBasis."

The Restricted Shares shall be held in custody by the Company until the
restrictions thereon shall have lapsed and, as a condition of any Award of
Restricted Shares, the Participant shall have delivered a stock power, endorsed
in blank, relating to the Common Stock covered by such Award.

10. UNFUNDED STATUS OF PLAN

         The Plan is intended to constitute an "unfunded" plan for incentive
compensation, and the Plan is not intended to constitute a plan subject to the
provisions of the Employee Retirement Income Security Act of 1974, as amended.
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. In its sole discretion,
the Committee may authorize the creation of trusts or other arrangements to meet
the obligations created under the Plan to deliver Stock or payments with respect
to Awards hereunder, PROVIDED, HOWEVER, that the existence of such trusts or
other arrangements is consistent with the unfunded status of the Plan.

11. NON-TRANSFERABILITY OF AWARDS

         Awards shall not be transferable, and no Award or interest therein may
be sold, transferred, pledged, assigned, or otherwise alienated or hypothecated,
other than by will or by the laws of descent and distribution. During the
Participant's life, all of a Participant's rights in any Award may be exercised
only by the Participant or the Participant's legal representative. Common Stock
with respect to which the Vesting Conditions are satisfied shall not be subject
to the transfer restrictions set forth in this Section.

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12. NO SPECIAL EMPLOYMENT OR OTHER RIGHTS

         Nothing contained in the Plan or in any Award shall confer upon any
recipient of an Award any right with respect to the continuation of his or her
employment or other association with the Surviving Corporation, the Company or
iBasis or interfere in any way with the right of the Surviving Corporation, the
Company or iBasis, subject to the terms of any separate employment or consulting
agreement or provision of law or corporate charter, certificate or articles, or
by-laws, to the contrary, at any time to terminate such employment or consulting
agreement or to increase or decrease, or otherwise adjust, the other terms and
conditions of the recipient's employment or other association with the Surviving
Corporation, the Company or iBasis.

13. NONEXCLUSIVITY OF THE PLAN

         The adoption of the Plan by the Board shall not be construed as
creating any limitations on the power of the Board to adopt such other incentive
arrangements as it may deem desirable, including without limitation, the
granting of stock options and restricted stock other than under the Plan, and
such arrangements may be either applicable generally or only in specific cases.

14. TERMINATION AND AMENDMENT OF THE PLAN

         The Board may at any time terminate the Plan or make such modifications
of the Plan as it shall deem advisable, subject to, during the period prior to
the Effective Time the prior written consent of iBasis. No amendment of the Plan
may adversely affect the terms of any Award outstanding on the date of such
amendment or alter the authority of the Committee. The Board may not terminate
the Plan if such termination shall adversely affect outstanding Awards. Subject
to the terms of Section 5 of the Plan, the Committee may amend the terms of any
Award theretofore granted, prospectively or retroactively, PROVIDED that the
Award as amended is consistent with the terms of the Plan, but no such amendment
shall adversely affect the rights of the recipient of such Award without his or
her consent.

15. RESERVATION OF STOCK

         The Company shall at all times during the term of the Plan and any
outstanding Award granted hereunder reserve or otherwise keep available such
number of shares of Stock as will be sufficient to satisfy the requirements of
the Plan (if then in effect) and the Awards and shall pay all fees and expenses
necessarily incurred by the Company in connection therewith.

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16. GOVERNING LAW

         The Plan and all Awards and actions taken thereunder shall be governed,
interpreted and enforced in accordance with the laws of the State of Delaware,
without regard to the conflict of laws principles thereof.