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                                                                  EXHIBIT 4.1

                                 AMENDMENT No. 1
                                       TO
                                RIGHTS AGREEMENT

This AMENDMENT No. 1 TO RIGHTS AGREEMENT (the "Amendment") is entered into as of
the 26th day of January, 2004, between Uni-Marts Inc., a Delaware corporation
(the "Company"), and Mellon Investor Services LLC, a New Jersey limited
liability company, as rights agent (the "Rights Agent"). Capitalized terms not
defined herein shall have the meanings given them in the Rights Agreements (as
defined below).

                                    RECITALS

WHEREAS, the Company and the Rights Agent are parties to a certain Rights
Agreement, dated as of February 6, 2002 (the "Rights Agreement").

WHEREAS, pursuant to Section 26 of the Rights Agreement, the Company and the
Rights Agent may, prior to the Distribution Date, amend any provision of the
Rights Agreement without the approval of any holders of Rights.

WHEREAS, to the knowledge of the Board of Directors of the Company, no event has
occurred that would cause the date of such event to constitute the Distribution
Date.

WHEREAS, the Board of Directors has determined that it is in the best interest
of the Company and its stockholders to amend the Rights Agreement as set forth
herein immediately prior to and in connection with the execution of (i) that
certain Agreement and Plan of Merger dated as of January 26, 2004, as the same
may be amended from time to time (the "Merger Agreement") among Green Valley
Acquisition Co., LLC, a Pennsylvania limited liability company ("Green Valley")
and the Company (pursuant to which Merger Agreement, among other things, the
Company shall merge with and into Green Valley (the "Merger")).

WHEREAS, the Company has requested that the Rights Agreement be amended in
accordance with Section 26 of the Rights Agreement, as set forth herein, and the
Rights Agent is willing to amend the Rights Agreement as set forth herein.

                                    AGREEMENT

NOW, THEREFORE, the parties, intending to be legally bound, hereby agree as
follows:


         1. Section 1(a) of the Rights Agreement is hereby amended to add the
following to the end of that Section:

         "Notwithstanding anything to the contrary contained in this Agreement,
         each of Green Valley Acquisition Co., LLC, a Pennsylvania limited
         liability company ("Green Valley"), any subsidiary of Green Valley, and
         any member, manager, officer, director, stockholder, employee or
         consultant of Green Valley or any



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         subsidiary of Green Valley (each, a "Buyer Affiliate") will not
         constitute an "Acquiring Person" for purposes of this Agreement as a
         result of (i) Green Valley's execution or performance of the Agreement
         and Plan of Merger dated as of January 26, 2004, as the same may be
         amended from time to time (the "Merger Agreement") among Green Valley
         and the Company, (ii) Green Valley's commencement of a tender offer in
         accordance with Section 7.6 of the Merger Agreement, (iii) the purchase
         or other receipt by Buyer or any Buyer Affiliate of additional shares
         of Common Stock of the Company at any time between the execution of the
         Merger Agreement and any termination of the Merger Agreement, or (iv)
         the execution by any Grandfathered Stockholder of a voting agreement
         with Green Valley, pursuant to which such Grandfathered Stockholder
         grants an irrevocable proxy to Green Valley or a Buyer Affiliate to
         vote in favor of the Merger Agreement and the Merger (as defined in the
         Merger Agreement)."

         2. Section 7(a) of the Rights Agreement is hereby amended to read in
its entirety as follows:

         "(a) The registered holder of any Right Certificate may exercise the
         Rights evidenced thereby (except as otherwise provided herein) in whole
         or in part at any time after the Distribution Date upon surrender of
         the Right Certificate, with the form of election to purchase on the
         reverse side thereof duly executed, to the Rights Agent at the office
         of the Rights Agent designated for such purpose, together with payment
         of the Purchase Price for each Fractional Share (or other securities,
         cash or other assets, as the case may be) as to which the Rights are
         exercised, at or prior to the earlier of (i) the Close of Business on
         the Final Expiration Date, (ii) the time at which the Rights are
         redeemed as provided in Section 23 (the "Redemption Date"), or (iii)
         immediately prior to the Effective Time (as defined in the Merger
         Agreement)."

         3. Section 34 of the Rights Agreement is hereby added as follows:

         "34. Green Valley Transactions. Notwithstanding any provision of this
         Rights Agreement to the contrary, no Distribution Date, Shares
         Acquisition Date, Section 11(a)(ii) Event or Section 13 Event shall be
         deemed to have occurred, neither Green Valley nor any Affiliate or
         Associate of Green Valley shall be deemed to have become an Acquiring
         Person and no holder of Rights shall be entitled to exercise such
         Rights under or be entitled to any rights pursuant to Section 7(a),
         11(a) or 13(a) of this Rights Agreement solely by reason of (x) the
         approval, execution, delivery or effectiveness of the Merger Agreement
         or (y) the consummation of the transactions contemplated under the
         Merger Agreement in accordance with the terms thereof (including,
         without limitation, the consummation of the merger of the Company with
         and into Green Valley (the "Merger")). Furthermore, upon the
         consummation of the Merger, this Rights Agreement shall automatically
         terminate."

         4. Upon the consummation of the transactions contemplated under the
Merger Agreement, the Company shall provide the Rights Agent with written notice
stating that



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(i) the transactions contemplated under the Merger Agreement have been
consummated in accordance with the terms thereof (including, without limitation,
the consummation of the merger of the Company with and into Green Valley) and
the Effective Time (as defined in the Merger Agreement) has occured, and (ii)
the Rights Agreement has been automatically terminated pursuant to its terms.

         5. This Amendment shall be deemed effective as of January 26, 2004 as
if executed by both parties on such date. Except as amended hereby, the Rights
Agreement shall remain unchanged and shall remain in full force and effect.

         6. This Agreement shall be deemed to be a contract made under the laws
of Delaware and for all purposes shall be governed by and construed in
accordance with the laws of such State applicable to contracts to be made and
performed entirely within such State, provided, however, that all provisions
regarding the rights, duties and obligations of the Rights Agent shall be
governed by and construed in accordance with the laws of the State of New York
applicable to contracts made and to be performed entirely within such State.

         7. This Amendment may be executed in any number of counterparts, each
of which shall be an original, but all of which together shall constitute one
instrument.

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IN WITNESS WHEREOF, the parties have caused this Amendment to be executed
themselves or by their respective duly authorized representatives as of the date
first above written.


                                          UNI-MARTS INC.



                                          By:  /S/ HENRY D. SAHAKIAN
                                             --------------------------------
                                               Name:  Henry D. Sahakian
                                               Title:   Chairman and CEO


                                          MELLON INVESTOR SERVICES LLC
                                          as Rights Agent



                                          By:  /S/ MITZI BRINKMAN
                                             ---------------------------------
                                               Name: Mitzi Brinkman
                                               Title:   Client Service Manager