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                                                                    EXHIBIT 3.31

                              AMENDED AND RESTATED
                                     BY-LAWS
                                       OF
                            CLARKSON INDUSTRIES, INC.

                                 ARTICLE I: NAME

          The name of the corporation is Clarkson Industries, Inc. (the
"Corporation").

                               ARTICLE II: OFFICES

          SECTION ONE. PRINCIPAL OFFICE. The principal office of the Corporation
in the State of New York shall be located in Syracuse.

          SECTION TWO. OTHER OFFICES. The Corporation may have such other
offices, either within or without the State of New York, as the Board of
Directors may determine from time to time.

                                ARTICLE III: SEAL

          The corporate seal shall have inscribed thereon the name of the
Corporation, the year of its organization, and the words "Corporate Seal, New
York." The seal may be used by causing it or a facsimile thereof to be impressed
or affixed or otherwise reproduced.

                                                                          [SEAL]

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                      ARTICLE IV: MEETINGS OF SHAREHOLDERS

          SECTION ONE. ANNUAL MEETING. An annual meeting of the shareholders for
the election of directors and for the transaction of such other business as may
properly come before the meeting shall be held at such date, place and time as
the Board of Directors may fix from time to time. If the day fixed for the
annual meeting is a legal holiday in the State of New York, the meeting shall be
held on the next succeeding business day. If the election of directors is not
held on the day designated, or at any adjournment thereof, the Board of
Directors shall cause the election to be held at a special meeting of the
shareholders as soon thereafter as is convenient.

          SECTION TWO. SPECIAL MEETINGS. Special meetings of the shareholders
may be held whenever called by the President. Special meetings shall be called
by the President, the Secretary or an Assistant Secretary whenever the holders
of at least ten percent (10%) of the number of outstanding shares of the voting
stock of the Corporation make written application for a meeting to the
Secretary.

          SECTION THREE. PLACE OF MEETING. The Board of Directors may designate
any place, either within or without the State of New York, as the place of
meeting for any annual meeting of shareholders or for any special meeting called
by the Board of Directors. If no designation is made, the place of meeting shall
be the principal office of the Corporation in the State of New York; but if all
of the shareholders shall meet at a time and place, either within or without the
State of New York, and consent to holding a meeting, any corporate action may be
taken at such meeting.

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          SECTION FOUR. NOTICE OF MEETINGS. Written notice stating the date,
place and time of any meeting of shareholders shall be given by or at the
direction of the President or the Secretary or any Assistant Secretary and
delivered, either personally or by first class mail, to each shareholder
entitled to vote at such meeting, not less than ten (10) nor more than fifty
(50) days before the date of such meeting. In the case of a special meeting, or
when required by statute or by these By-Laws, the purpose or purposes for which
a meeting is called shall be stated in the notice. If mailed, the notice of a
meeting shall be deemed to be delivered when deposited in the United States
mail, postage prepaid, addressed to the shareholder at the address as it appears
on the records of the Corporation.

          SECTION FIVE. ACTION WITHOUT A MEETING. Any action required by law or
permitted to be taken at a meeting of the shareholders may be taken without a
meeting if a consent in writing, setting forth the action so taken, shall be
signed by all of the shareholders entitled to vote thereon or their respective
proxies.

          SECTION SIX. QUORUM. Shareholders holding a majority of the
outstanding shares of voting stock shall constitute a quorum at any meeting of
shareholders. If a quorum is not present at any meeting of shareholders, a
majority of the shareholders present may adjourn the meeting from time to time
without further notice.

          SECTION SEVEN. VOTING. Each shareholder shall at every meeting of
shareholders be entitled to one vote for each share of Stock owned by such
shareholder in person or by proxy. At any meeting of the shareholders, a
shareholder entitled to vote may vote by proxy executed in writing by the
shareholder or by the shareholder's duly authorized

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attorney-in-fact. No proxy shall be valid after eleven (11) months from the date
of its execution, unless otherwise provided in the proxy.

          Except as otherwise required by statute, by the Certificate of
Incorporation, by these By-Laws or by mutual agreement in writing of all of the
shareholders, all matters coming before any meeting of the shareholders shall be
decided by the vote of the holders a majority of the number of shares of Stock
present in person or by proxy at the meeting and entitled to vote thereon. At
all elections of directors, the voting may, but need not be, by ballot, and the
persons receiving the greatest number of votes shall be the directors of the
Corporation.

          SECTION EIGHT. RECORD DATE. In order to determine which shareholders
are entitled to notice of, or to vote at, any meeting of shareholders, or in
order to make a determination of shareholders for any other proper purpose, the
Board of Directors may fix in advance a date as record date, which shall be not
less than ten (10) days nor more than fifty (50) days prior to the meeting.

                          ARTICLE V: BOARD OF DIRECTORS

          SECTION ONE. GENERAL POWERS. Subject to the provisions of the New York
Business Corporation Law and the regulations adopted thereunder, and subject to
any limitations in the Certificate of Incorporation of the Corporation relating
to action required to be approved by the shareholders, the business and affairs
of the Corporation shall be managed, and all corporate powers shall be exercised
by or under, the direction of the Board of Directors. The Board may delegate the
management of the day-to-day operation of the

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business of the Corporation to the officers or to a management company or other
person, provided that the business and affairs of the Corporation shall be
managed and all corporate powers shall be exercised under the ultimate direction
of the Board.

          SECTION TWO. NUMBER. The number of directors who will constitute the
entire Board of Directors shall be not less than three, except that where all
the shares of the stock of the Corporation are owned beneficially and of record
by less than three shareholders, the number of directors may be less than three
but not less than the number of shareholders. Subject to the preceding sentence,
the number of directors may be increased or decreased by the Board of Directors.
No decrease in the number of directors shall affect the term of office of any
director previously elected or designated.

          SECTION THREE. ELECTION. Members of the initial Board of Directors
elected at the organizational meeting shall hold office until the first annual
meeting of shareholders and until their respective successors shall have been
duly elected and qualified.

          SECTION FOUR. VACANCIES. Any vacancy occurring in the Board of
Directors for any reason, and any directorship to be filled by reason of an
increase in the number of directors, may be filled by the vote of a majority of
the remaining directors even if the number of such directors does not constitute
a quorum. A director so selected to fill a vacancy shall serve for the unexpired
term of his predecessor in office.

          SECTION FIVE. REMOVAL. Any or all of the directors may be removed,
with or without cause, at any time by the vote of the holders of at least a
majority of the shares of the outstanding voting stock of the Corporation at a
special meeting called for that purpose.

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          SECTION SIX. REGULAR MEETING. An annual regular meeting of the Board
of Directors shall be held following the annual meeting of the shareholders of
the Corporation, or at such other date, time and place as may be fixed in the
manner hereinafter provided or as specified in a duly executed waiver of notice
thereof. Other regular meetings of the Board of Directors may be held without
notice, at such time and date as shall be fixed by the Board, at the principal
office of the Corporation or at such other place as the Board of Directors shall
have previously provided by resolution. The President and the Chairman of the
Board, if any, may change the date, time or place of any such regular meeting,
in which event, written notice of the new date, time and/or place shall be given
to each director at least seven (7) days before the date of such meeting (unless
waived at any time before or after the meeting). Attendance at a meeting without
protesting, prior thereto or at its commencement, shall constitute a waiver of
notice. The Board of Directors may dispense with the holding of any regular
meeting.

          SECTION SEVEN. SPECIAL MEETINGS. Special meetings of the Board of
Directors may be called by or at the request of the President, the Chairman of
the Board, if any, or any director. Unless all of the directors agree on a
different location, special meetings shall be held at the office of the
Corporation.

          SECTION EIGHT. NOTICE. Notice of any special meeting of the Board of
Directors shall be given at least ten days prior thereto by written notice
delivered personally or sent by nationally-utilized overnight delivery service
or first class mail or by transmitting such notice with confirmed delivery
(including, by facsimile or other form of recorded communication, provided that
delivery of such notice in written form is confirmed in writing) to each
director

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at the director's address as shown on the records of the Corporation. If mailed,
such notice shall be deemed to be delivered when deposited in the United States
mail, postage prepaid. Any director may at any time waive notice of any meeting
to the extent permitted in these By-Laws. The attendance of a director at any
meeting shall constitute a waiver of notice of such meeting, except where a
director attends the meeting for the express purpose of objecting to the
transaction of any business because the meeting was not lawfully called or
convened. The business to be transacted at the meeting need not be specified in
the notice of such meeting, unless specifically required by law or by these
By-Laws.

          SECTION NINE. QUORUM. A majority of the Board of Directors shall
constitute a quorum for the transaction of business at any meeting of the Board.
If less than a majority of the directors are present at a meeting, a majority of
those directors present may adjourn the meeting from time to time without
further notice.

          SECTION TEN. PARTICIPATION IN MEETINGS BY ELECTRONIC MEANS. Members of
the Board of Directors or any committee of the Board may participate in any
meeting of the Board or of such committee by means of a conference telephone or
similar communications equipment, provided such equipment enables all persons
participating in the meeting to hear one another. Participation in a meeting
pursuant to this provision shall constitute presence in person at such meeting.

          SECTION ELEVEN. MANNER OF ACTING. The act of a majority of the
directors present at a meeting at which a quorum is present shall be the act of
the Board of Directors, unless the act of a greater number is required by law or
by these By-Laws.

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          SECTION TWELVE. ACTION WITHOUT A MEETING. Unless otherwise restricted
by the Certificate of Incorporation or these By-Laws, any action required or
permitted to be taken by the Board of Directors or any committee thereof may be
taken without a meeting if all members of the Board of Directors or the
committee, as the case may be, consent in writing to the adoption of a
resolution authorizing the action. The resolution and the written consents
thereto shall be filed with the minutes of the proceedings of the Board or
committee.

                              ARTICLE VI: OFFICERS

          SECTION ONE. OFFICERS. The officers of the Corporation shall be a
President, one or more Vice Presidents (the number thereof to be determined by
the Board of Directors), a Secretary, a Treasurer, and such other officers as
may be elected in accordance with the provisions of this article. The Board of
Directors may elect or appoint such other officers, including one or more
Assistant Secretaries and one or more Assistant Treasurers, as it shall deem
desirable, and such officers shall have the authority and perform the duties
prescribed from time to time by the Board of Directors. Any two or more offices
may be held by the same person.

          SECTION TWO. ELECTION AND TERM OF OFFICE. The officers of the
Corporation shall be elected annually by the Board of Directors at the annual
meeting of the Board of Directors. If the election of officers is not held at
such meeting, it shall be held as soon thereafter as is convenient. New offices
may be created and filled at any meeting of the Board of Directors. Each officer
shall hold office until a successor shall have been duly elected and

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shall have been qualified. The Board may require any officer to give security
for the faithful performance of his duties.

          SECTION THREE. REMOVAL. Any officer elected or appointed by the Board
of Directors may be removed by the Board of Directors whenever in its judgment
the best interests of the Corporation would be served thereby.

          SECTION FOUR. VACANCIES. A vacancy in any office, because of death,
resignation, removal, disqualification or otherwise, may be filled by the Board
of Directors for the unexpired portion of the term.

          SECTION FIVE. CHAIRMAN OF THE BOARD. If one is appointed, the Chairman
of the Board shall preside at all meetings of the Board of Directors and, in
general, shall perform all duties incident to the office of the Chairman of the
Board and such other duties as may be prescribed by the Board from time to time.
The Chairman of the Board shall have the power to call meetings of the Board of
Directors. Only members of the Board of Directors shall be qualified to be
elected to the office of Chairman of the Board.

          SECTION SIX. PRESIDENT. The President shall be the principal executive
officer of the Corporation and shall, in general, supervise and control the
business and affairs of the Corporation. When requested by the Chairman of the
Board, if any, the President shall attend all meetings of the Board of
Directors. The President may sign any and all deeds, mortgages, bonds,
contracts, or other instruments that the Board of Directors has authorized to be
executed, except in cases where the signing and execution thereof shall be
expressly delegated by the Board of Directors, by these By-Laws or by statute to
some other officer or agent of the

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Corporation; and, in general, the President shall perform all duties incident to
the office of president and such other duties as may be prescribed by the Board
of Directors from time to time.

          SECTION SEVEN. VICE-PRESIDENT. In the absence of the President or in
the event of the President's inability or refusal to act, the Vice President
shall perform the duties of the President, and when so acting, shall have all
the powers of and be subject to all the restrictions imposed upon the President.
Any Vice President shall perform such other duties as from time to time may be
assigned to that Vice President by the President or by the Board of Directors.

          SECTION EIGHT. TREASURER. If required by the Board of Directors, the
Treasurer shall give a bond for the faithful discharge of the duties of
Treasurer in such sum and with such surety or sureties as the Board of Directors
shall determine. The Treasurer shall have charge and custody of, and be
responsible for, all funds and securities of the Corporation; receive and give
receipts for amounts due and payable to the Corporation from any source
whatsoever, and deposit all such amounts in the name of the Corporation in such
banks, trust companies or other depositories as the Board of Directors select;
and, in general, perform all duties incident to the office of Treasurer and such
other duties as from time to time may be assigned to the Treasurer by the
President or by the Board of Directors.

          SECTION NINE. SECRETARY. The Secretary shall keep the minutes of the
meetings of the Board of Directors; see that all notices are duly given in
accordance with the provisions of these By-Laws or as required by law; be
custodian of the corporate records and the seal of the Corporation and see that
the seal of the Corporation is affixed to all documents, the

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execution of which on behalf of the Corporation under its seal is duly
authorized in accordance with the provisions of these By-Laws; keep a register
of the post office address of each shareholder which each such shareholder shall
furnish to the Secretary; and in general perform all duties incident to the
office of Secretary and such other duties as from time to time may be assigned
to the Secretary by the President or by the Board of Directors.

          SECTION TEN. ASSISTANT SECRETARY. If one is elected, the assistant
secretary shall have such powers and perform such duties as the president,
secretary or the Board of Directors may from time to time assign and shall
perform such other duties as may be prescribed by these By-Laws. At the request
or the absence or inability to act of the secretary, the assistant secretary
shall perform the duties of the secretary and, when so acting, shall have all of
the powers of, and be subject to all of the restrictions upon, the secretary.

                             ARTICLE VII: COMMITTEES

          SECTION ONE. COMMITTEES OF DIRECTORS. The Board of Directors, by
resolution adopted by a majority of the entire Board, may designate from among
its members one or more committees, each consisting of three or more directors
and each of which, to the extent provided in the resolution, shall have and
exercise the authority of the Board of Directors in the management of the
business, property and affairs of the Corporation; PROVIDED, HOWEVER, that no
committee of the Board of Directors shall have the authority to:

          (a)  amend, alter or repeal the By-Laws;

          (b)  elect, appoint or remove any member of any such committee or any
               director or officer of the Corporation;

          (c)  amend the Certificate of Incorporation;

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                           ARTICLE VIII: CAPITAL STOCK

          SECTION ONE. CONSIDERATION AND PAYMENT. The capital stock may be
issued for such consideration as may be fixed from time to time by the Board of
Directors; PROVIDED, HOWEVER, that the consideration may not be less than the
par value of any such stock having par value. Payment of such consideration may
be made, in whole or in part, in (a) cash, securities or other property of any
description, or any interest therein, (b) labor or services rendered to or for
the benefit of the Corporation, or (c) shares, securities or other obligations
of the Corporation actually surrendered, cancelled or reduced. No certificate
shall be issued for any shares until such shares are fully paid.

          SECTION TWO. CERTIFICATES REPRESENTING SHARES. Shares of the Capital
Stock of the Corporation shall be represented by certificates signed by the
Chairman, if any, or the President or a Vice President and the Secretary or an
Assistant Secretary or the Treasurer or an Assistant Treasurer, except that such
signatures may be facsimile if the certificate is countersigned by a transfer
agent or registered by a registrar other than the Corporation or its employee.
Upon each such certificate shall appear such legend or legends as may be
required by law or by any contract or agreement to which the Corporation is a
party. No certificate shall be valid without the signatures and legends required
hereby.

          SECTION THREE. LOST CERTIFICATES. The Board of Directors may direct
the Corporation to issue a new certificate in place of any certificate
theretofore issued by the Corporation which is alleged to have been lost or
destroyed. When authorizing the issuance of a new certificate, the Board of
Directors, in its discretion and as a condition precedent to the issuance

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thereof, may prescribe such terms and conditions as it deems expedient, and may
require such indemnities as it deems adequate, to protect the Corporation from
any claim that may be made against it with respect to any such certificate
alleged to have been lost or destroyed.

          SECTION FOUR. TRANSFER OF STOCK. The Corporation or its transfer agent
shall register a transfer of a stock certificate, issue a new certificate and
cancel the old certificate upon presentation for transfer of a stock
certificate, duly endorsed or accompanied by proper evidence of succession,
assignment or authority to transfer if there has been compliance with any
applicable tax law relating to the collection of taxes and after the Corporation
or its agent has discharged any duty to inquire into any adverse claims of which
the Corporation or agent has notice. Notwithstanding the foregoing, no such
transfer shall be effected by the Corporation or its transfer agent if such
transfer is prohibited by law, by the Certification of Incorporation by these
By-Laws or by any contract or agreement to which the Corporation is a party.

                       ARTICLE IX: DIVIDENDS AND RESERVES

          SECTION ONE. DIVIDENDS. To the extent permitted by law and subject to
any limitations or conditions contained in the Certificate of Incorporation,
dividends may be declared by a resolution duly adopted by the Board of
Directors and may be paid in cash, property or in shares of the capital stock of
the Corporation.

          SECTION TWO. RESERVES. Before payment of any dividend, the Board of
Directors may set aside out of any funds available for dividends such sum or
sums as the

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Board of Directors, in its absolute discretion, may determine as a reserve or
reserves to meet contingencies, to equalize dividends, to repair or maintain
property or to serve other purposes conducive to the interests of the
Corporation. The directors may modify or abolish any such reserve in the manner
in which it was created.

                            ARTICLE X: MISCELLANEOUS

          SECTION ONE. BOOKS AND RECORDS. The Corporation shall keep correct and
complete books and records of account and shall also keep minutes of the
proceedings of its shareholders, Board of Directors, and committees having any
of the authority of the Board of Directors. It shall keep at its principal
office a list or record containing the names and addresses of all shareholders,
the number of stock certificates held by each and the dates when they
respectively became the holders of record thereof.

          Any person who shall have been a shareholder of record of the
Corporation for at least six (6) months, or any person holding, or authorized in
writing by the holders of, at least five percent (5%) of the number of shares of
outstanding stock, upon at least five (5) days' written demand, shall have the
right, to examine in person or by agent or attorney, during usual business
hours, the minutes of the proceedings of the shareholders and the list or record
of shareholders, and to make extracts therefrom.

          SECTION TWO. CHECKS. All checks or demands for money and notes or
other instruments evidencing indebtedness or obligations of the Corporation
shall be signed by such officer or officers or such other person or persons as
the Board may from time to time

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designate.

          SECTION THREE. FISCAL YEAR. The fiscal year of the Corporation shall
begin on the first day of January and end on the last day of December in each
year.

          SECTION FOUR. WAIVER OF NOTICE. Whenever any notice is required to be
given under the provisions of the New York Business Corporation Law or under the
provisions of the Certificate of Incorporation or the By-Laws of the
Corporation, a waiver thereof in writing signed by the person or persons
entitled to such notice, whether before or after the time stated therein, shall
be deemed equivalent to the giving of such notice.

                          ARTICLE XII: INDEMNIFICATION

          The Corporation shall indemnify and reimburse any director or officer
of the Corporation and any such person's testator or intestate to the fullest
extent permitted by Sections 722 and 723 of the Business Corporation Law of the
State of New York, including any amendments to or substitutions for such
Sections 722 and 723 which may be made from time to time.

                            ARTICLE XIII: AMENDMENTS

          The shareholders may amend or repeal these By-laws or adopt new
by-laws.

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