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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
February 14, 2003, between LTX Corporation, a Massachusetts corporation (the
"Company"), and EquiServe Trust Company, N.A., as Rights Agents (the "Rights
Agent"). Capitalized terms not otherwise defined herein shall have the meanings
given them in the Rights Agreement dated as of April 30, 1999, between the
parties hereto.

                                    RECITALS

WHEREAS, the Board of Directors of the Company has determined that it is in the
best interests of the Company to amend the Rights Agreement to modify the
definition of Acquiring Person to exclude a certain stockholder that
inadvertently became the beneficial owner of more than 15% of the Common Stock
of the Company from such definition in specified circumstances; and

WHEREAS, the Company has determined that the Rights Agreement be amended in
accordance with Section 27 of the Rights Agreement, as set forth herein, and the
Rights Agent is hereby directed to join in the amendment to the Rights Agreement
as set forth herein.

                                    AGREEMENT

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

1.   Section 1(a) of the Rights Agreement is hereby amended to read in its
     entirety as follows:

     (a)  "Acquiring Person" shall mean any Person who or which, together with
          all Affiliates and Associates of such Person, shall be the Beneficial
          Owner of 15% or more of the shares of Common Stock then outstanding,
          but shall not include (i) the Company, (ii) any Subsidiary of the
          Company, (iii) any employee benefit plan of the Company or of any
          Subsidiary of the Company, (iv) any Person organized, appointed or
          established by the Company for or pursuant to the terms of any such
          plan, or (v) an Exempted Person. Notwithstanding the foregoing, (x) if
          the Board determines in good faith that a Person who would otherwise
          be an "Acquiring Person", as defined pursuant to the foregoing
          provisions of this paragraph (a), has become such inadvertently, and
          such Person divests as promptly as practicable a sufficient number of
          shares of Common Stock so that such Person would no longer be an
          "Acquiring Person", as defined pursuant to the fore going provisions
          of this paragraph (a), then such Person shall not be deemed to be an
          "Acquiring Person" for any purposes of this Agreement unless and until
          such Person shall again become an "Acquiring Person" and (y) any such
          Person who becomes the Beneficial Owner of fifteen percent (15%) or
          more of the shares of the Common Stock then outstanding as a result of
          a reduction in the number of shares of Common Stock then outstanding
          due to the repurchase of shares of Common Stock by the Company shall
          not be deemed to be an "Acquiring Person" for any purposes of this
          Agreement unless and until such Person, after becoming aware that such
          Person has become the Beneficial Owner of fifteen percent (15%) or
          more of the shares of Common Stock then outstanding, acquires
          beneficial ownership of any additional shares of Common Stock (other
          than by means of a stock dividend or stock split)."


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2.   Section 1(ff) of the Rights Agreement is hereby added as follows:

     (ff) "Exempted Person" shall mean:

     (i)  Capital Group International Inc., together with all of its Affiliates
          and Associates ("Capital Group International"), which as of the date
          of this Amendment reported that it is the Beneficial Owner of more
          than 15% of the Company's Common Stock then outstanding, unless and
          until the earlier of such time as Capital Group International,
          directly or indirectly, becomes the Beneficial Owner of (x) more than
          17% of the Common Stock then outstanding (other than under
          circumstances described in the second sentence of Section 1(a) hereof
          (replacing for purposes of this clause (x) all references in Section
          1(a) to 15% with 17%)) or (y) less than 15% of the Common Stock then
          outstanding, in either of which event, Capital Group International
          immediately shall cease to be an Exempted Person;

3.   Except as amended hereby, the Rights Agreement shall remain unchanged and
     shall remain in full force and effect.

4.   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 by
their respective duly authorized representatives as of the date first above
written.

LTX CORPORATION

By:    /s/ Mark J. Gallenberger
       -----------------------------
Name:  Mark J. Gallenberger
Title: Vice President and Chief Financial Officer

EQUISERVE TRUST COMPANY, N.A., RIGHTS AGENT (as successor to Bank Boston, N.A.)

By:    /s/ Margaret M. Prentice
       -----------------------------
Name:  Margaret M. Prentice
Title: Managing Director