Document:

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                                                                   Exhibit 4.5.1

                                 AMENDMENT NO. 1
                                       TO
                         RPM, INC. 401(k) TRUST AND PLAN

     This Amendment No. 1 is executed as of the date set forth below by RPM,
Inc. (hereinafter called the "Company");

                                   WITNESSETH:

     WHEREAS, the Company maintains the RPM, Inc. 401(k) Trust and Plan
(hereinafter called the "Trust and Plan") for the benefit of certain eligible
employees of Participating Companies; and

     WHEREAS, it is the desire of the Company to amend the Trust and Plan to
reflect that future matching contributions will be made in cash rather than
Company stock, to permit Participants to direct the investment of a portion of
future employee and matching contributions in Company stock and to permit
Accountholders to transfer amounts out of the Pre-Tax Contribution Stock Fund
and Matching Contribution Stock Fund into other investment funds; and

     WHEREAS, the Company reserved the right to amend the Trust and Plan
pursuant to Section 21.1 thereof;

     NOW, THEREFORE, pursuant to Section 21.1 of the Trust and Plan, the Company
hereby amends the Trust and Plan, effective as of October 1, 2002, as follows:

     1.   Section 5.3 of the Trust and Plan is hereby amended by the deletion of
said Section 5.3 and the substitution in lieu thereof of the following:

          5.3   Payment to the Trustee.

                The Participating Companies shall make the contributions
     specified in Sections 5.1 and 5.2 hereof to the Trustee in cash not later
     than the last day upon which

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     the Participating Company may make a contribution under this Trust and Plan
     and secure under the Code a deduction of such contribution in the
     computation of its Federal income taxes for the Taxable Year for which such
     contribution is made.

     2.   Sections 7.7 and 7.8 of the Trust and Plan are hereby amended by the
deletion of said Sections 7.7 and 7.8 and the substitution in lieu thereof of
the following:

          7.7   Maintenance of Pre-Tax Contribution Stock Fund.

                The Trustee shall maintain a Pre-Tax Contribution Stock Fund
     within the Trust Fund. Prior to June 1, 1996, pre-tax contributions made by
     the Participating Companies on a Participant's behalf and contributed to
     the Trust and Plan pursuant to the provisions of the Trust and Plan at such
     time and all dividends and other amounts attributable to such pre-tax
     contributions that were made in cash and used to purchase Shares shall
     continue to be held and invested in the Pre-Tax Contribution Stock Fund,
     subject to the diversification provisions of Section 7.15 hereof. On and
     after June 1, 1996 and prior to October 1, 2002, Accountholders were no
     longer permitted to direct the investment of amounts credited to their
     Pre-Tax Accounts into the Pre-Tax Contribution Stock Fund.

          On and after October 1, 2002, an Accountholder may, in accordance with
     Section 7.16 hereof, direct that a portion of the pre-tax contributions
     made on his behalf be held and invested in the Pre-Tax Contribution Stock
     Fund.

          7.8   Maintenance of Matching Contribution Stock Fund.

                The Trustee shall maintain a Matching Contribution Stock Fund
     within the Trust Fund. Prior to October 1, 2002, matching contributions
     made by the Participating Companies on a Participant's behalf and
     contributed to the Trust and Plan pursuant to the

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     provisions of the Trust and Plan at such time and all dividends and other
     amounts attributable to such matching contributions that were made in
     Shares or made in cash and used to purchase Share shall continue to be held
     and invested in the Matching Contribution Stock Fund, subject to the
     diversification provisions of Section 7.15 hereof.

          On and after October 1, 2002, an Accountholder may, in accordance with
     Section 7.16 hereof, direct that the matching contributions made on his
     behalf be held and invested in the Matching Contribution Stock Fund.

     3.   Section 7.10 of the Trust and Plan is hereby deleted and the following
is substituted therefor:

          7.10  [RESERVED]

     4.   Section 7.15 of the Trust and Plan is hereby amended by the deletion
of said Section 7.15 and the substitution in lieu thereof of the following:

          7.15  Diversification Of Investments.

                An Accountholder may elect to sell the Shares, if any, credited
     to his Pre-Tax Contribution Stock Fund or Matching Contribution Stock Fund
     at any time and to direct the investment of the proceeds from such sale
     into any other investment fund established hereunder. Any such direction
     shall be made in accordance with the provisions of this Article 7.
     Accountholders may not elect to invest in Shares in any investment fund
     hereunder except as permitted in Section 7.16 below. Accountholders may not
     elect to invest in Shares through the Pre-Tax Contribution Stock Fund or
     Matching Contribution Stock Fund by transferring amounts from other
     investment funds into said stock funds.

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     5.   Article 7 of the Trust and Plan is hereby amended by the addition
thereto of a new Section 7.16 to read as follows:

          7.16  Procedures for Direction of Investment in Company Stock Funds.

                On and after October 1, 2002, an Accountholder may direct the
     Trustee to invest up to twenty percent (20%) of his pre-tax and matching
     contributions made to the Trust and Plan in the Pre-Tax Contribution Stock
     Fund and Matching Contribution Stock Fund. An Accountholder may only invest
     in Shares through the Pre-Tax Contribution Stock Fund and Matching
     Contribution Stock Fund for pre-tax and matching contributions made on or
     after October 1, 2002. All such directions shall be deemed to be continuing
     directions until they shall have been changed. Any such changes shall be
     made in accordance with the provisions of Sections 7.4 and 7.5 hereof.
     Amounts invested and held in the Pre-Tax Contribution Stock Fund and the
     Matching Contribution Stock Fund, pursuant to this Section, shall be
     subject to the diversification requirements of Section 7.15 hereof.

     IN WITNESS WHEREOF, the Company, by its duly authorized officers, has
executed this Amendment No. 1 this 27th day of August, 2002.

                                               RPM, Inc.

                                                    ("Company")

                                               By:  /s/ Ronald A. Rice
                                                    ----------------------------

                                               And: /s/ Keith R. Smiley
                                                    ----------------------------

                                       4<PAGE>
                                                                   Exhibit 4.5.2

                                 AMENDMENT NO. 2
                                       TO
                         RPM, INC. 401(k) TRUST AND PLAN

     This Amendment No. 2 is executed by RPM, Inc. (hereinafter called the
"Company") and acknowledged by RPM International Inc. (hereinafter called the
"Successor Company"), as of the dates set forth below.

                                   WITNESSETH:

     WHEREAS, the Company maintains the RPM, Inc. 401(k) Trust and Plan
(hereinafter called the "Trust and Plan") for the benefit of certain eligible
employees of Participating Companies; and

     WHEREAS, in connection with the reincorporation of the Company as a
Delaware corporation, the Company has agreed to assign, and the Successor
Company has agreed to assume, all of the powers, authorities, duties,
responsibilities and obligations of the Company with respect to the Trust and
Plan in accordance with an Agreement and Plan of Merger dated August 29, 2002;
and

     WHEREAS, it is the desire of the Company to amend the Trust and Plan in
order to reflect the reincorporation of the Company, the assumption of the Trust
and Plan by the Successor Company, and the new name of the Trust and Plan, all
of which shall become effective at 9:00 a.m. on October 15, 2002 (the "Effective
Time"); and

     WHEREAS, the Company reserved the right to amend the Trust and Plan
pursuant to Section 21.1 thereof;

     NOW, THEREFORE, pursuant to Section 21.1 of the Trust and Plan, the Company
hereby amends the Trust and Plan, effective as of the Effective Time, as
follows:

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     1.   The name of the Trust and Plan is hereby changed to the "RPM
International Inc. 401(k) Trust and Plan."

     2.   The Trust and Plan is hereby amended by the deletion of each reference
to the term "RPM, Inc." as a corporate entity, including but not limited to the
definition of the term "Company" in Section 2.12, and the substitution in lieu
thereof of the term "RPM International Inc." as the corporate entity.

     3.   The Trust and Plan is hereby amended by the deletion of each reference
to the term "RPM, Inc." as the sponsor of certain employee benefit plans,
including but not limited to the following employee benefit plans: the RPM, Inc.
401(k) Trust and Plan in Section 1.1, the RPM, Inc. Retirement Plan in Section
2.15, and the RPM, Inc. Union 401(k) Retirement Savings Trust and Plan in
Section 23.1, and the substitution in lieu thereof of the term "RPM
International Inc." as the sponsor of such plans.

     4.   The Trust and Plan is hereby amended by the deletion of each reference
to RPM, Inc. as an Ohio corporation in every instance that it appears, including
but not limited to p. iv and the substitution in lieu thereof of the reference
to RPM International Inc. as a Delaware corporation.

                            [Signature Page Follows]

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     IN WITNESS WHEREOF, the Company, by its officers duly authorized, has
executed this Amendment No. 2 this 14th day of October, 2002.

                                    RPM, INC.

                                    By: /s/ P. Kelly Tompkins
                                        ----------------------------------------
                                        P. Kelly Tompkins, Secretary

     The Successor Company hereby acknowledges its assumption of all of the
powers, authorities, duties, responsibilities and obligations of the Company
with respect to the Trust and Plan as of the Effective Time.

                                    RPM INTERNATIONAL INC.

                                    By: /s/ Keith R. Smiley
                                        ----------------------------------------
                                        Keith R. Smiley, Treasurer and
                                          Assistant Secretary

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