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                                                                    EXHIBIT 99.4

            GUIDELINES FOR CERTIFICATION OF TAXPAYER IDENTIFICATION
                         NUMBER ON SUBSTITUTE FORM W-9

    GUIDELINES FOR DETERMINING THE PROPER IDENTIFICATION NUMBER TO GIVE THE
PAYOR.--Social Security numbers have nine digits separated by two hyphens: i.e.
000-00-0000. Employer identification numbers have nine digits separated by only
one hyphen: i.e. 00-0000000. The table below will help determine the number to
give the payer.

<Table>
<Caption>
- --------------------------------------------------
                       
                          GIVE THE
                          TAXPAYER
FOR THIS TYPE OF          IDENTIFICATION
ACCOUNT:                  NUMBER OF--
- --------------------------------------------------

1. An individual's        The individual
account

2. Two or more            The actual owner of the
   individuals (joint     account, or if combined
   account)               funds, the first
                          individual on the
                          account (1)

3. Custodian account of   The minor (2)
   a minor (Uniform Gift
   to Minors Act)

4. Adult and minor        The adult or, if the
   (joint account)        minor is the only
                          contributor, the
                          minor (1)

5. Account in the name    The ward, minor, or
   of guardian or         incompetent person (3)
   committee for a
   designated ward,
   minor, or incompetent

6. a. The usual           The grantor-trustee (1)
      revocable savings
      trust account
      (grantor is also
      trustee)

  b. So-called trust      The actual owner (1)
     account that is not
     a legal or valid
     trust under state
     law

7. Sole proprietorship    The owner (4)
   account

- --------------------------------------------------

<Caption>
- --------------------------------------------------
                          GIVE THE
                          TAXPAYER
                          IDENTIFICATION
FOR THIS TYPE OF ACCOUNT: NUMBER OF--
- --------------------------------------------------
                       

 8. A valid trust,        The legal entity (Do not
    estate, or pension    furnish the identifying
    trust                 number of the personal
                          representative or
                          trustee unless the legal
                          entity itself is not
                          designated in the
                          account title.) (5)

 9. Corporate account     The corporation

10. Religious,            The organization
    charitable, or
    educational
    organization account

11. Partnership account   The partnership
    held in the name of
    the business

12. Association, club,    The organization
    or other tax-exempt
    organization

13. A broker or           The broker or nominee
    registered nominee

14. Account with the      The public entity
    Department of
    Agriculture in the
    name of a public
    entity (such as a
    State or local
    government, school
    district or prison)
    that receives
    agricultural program
    payments
- --------------------------------------------------
</Table>

(1) List first and circle the name of the person whose number you furnish. If
    only one person in a joint account has a social security number, that
    person's number must be furnished.

(2) Circle the minor's name and furnish the minor's social security number.

(3) Circle the ward's, minor's or incompetent person's name and furnish such
    person's social security number.

(4) Show your individual name. Below your individual name, enter your business
    or "doing business as" name" if you have one. You may use either your social
    security number or your business' employer identification number.

(5) List first and circle the name of the legal trust, estate or pension trust.

NOTE:  IF NO NAME IS CIRCLED WHEN THERE IS MORE THAN ONE NAME, THE NUMBER WILL
       BE CONSIDERED TO BE THAT OF THE FIRST NAME LISTED.
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         GUIDELINES FOR CERTIFICATION OF TAXPAYER IDENTIFICATION NUMBER
                             ON SUBSTITUTE FORM W-9
                                     PAGE 2

    Note: Section references are to the Internal Revenue Code unless otherwise
noted.

OBTAINING A NUMBER

    If you do not have a taxpayer identification number or you don't know your
number, obtain Form SS-5, Application for a Social Security Number Card (for
individuals), or Form SS-4, Application for Employer Identification Number (for
businesses and all other entities), at the local office of the Social Security
Administration or the Internal Revenue Service (the "IRS") and apply for a
number.

PAYEES EXEMPT FROM BACKUP WITHHOLDING

    Payees specifically exempted from backup withholding on ALL payments include
the following:

    - A corporation.

    - A financial institution.

    - An organization exempt from tax under section 501(a), or an individual
      retirement plan.

    - The United States or any agency or instrumentality thereof.

    - A State, the District of Columbia, a possession of the United States, or
      any subdivision or instrumentality thereof.

    - A foreign government, a political subdivision of a foreign government, or
      any agency or instrumentality thereof.

    - An international organization or any agency, or instrumentality thereof.

    - A registered dealer in securities or commodities registered in the U.S. or
      a possession of the U.S.

    - A real estate investment trust.

    - A common trust fund operated by a bank under section 584(a).

    - An exempt charitable remainder trust, or a non-exempt trust described in
      section 4947(a)(1).

    - An entity registered at all times under the Investment Company Act of
      1940.

    - A foreign central bank of issue.

    Payments of dividends and patronage dividends not generally subject to
backup withholding include the following:

    - Payments to nonresident aliens subject to withholding under section 1441.

    - Payments to partnerships not engaged in a trade or business in the U.S.
      and which have at least one nonresident partner.

    - Payments of patronage dividends where the amount received is not paid in
      money.

    - Payments made by certain foreign organizations.

    - Payments made to a nominee.

    Payments of interest not generally subject to backup withholding include the
following:

    - Payments of interest on obligations issued by individuals. Note: You may
      be subject to backup withholding if this interest is $600 or more and is
      paid in the course of the payer's trade or business and you have not
      provided your correct taxpayer identification number to the payer.

    - Payments of tax-exempt interest (including exempt-interest dividends under
      section 852).

    - Payments described in section 6049(b)(5) to non-resident aliens.

    - Payments on tax-free covenant bonds under section 1451.

    - Payments made by certain foreign organizations.

    - Payments made to a nominee.

    Exempt payees described above should file Form W-9 to avoid the possible
erroneous backup withholding. FILE THIS FORM WITH THE PAYER, FURNISH YOUR
TAXPAYER IDENTIFICATION NUMBER, WRITE "EXEMPT" ON THE FACE OF THE FORM, AND
RETURN IT TO THE PAYER. IF THE PAYMENTS ARE INTEREST, DIVIDENDS, OR PATRONAGE
DIVIDENDS, ALSO SIGN AND DATE THE FORM.

    Certain payments other than interest, dividends, and patronage dividends,
that are not subject to information reporting are also not subject to backup
withholding. For details, see the regulations under sections 6041, 6041(a),
6042, 6044, 6045, 6049, 6050A and 6050N.

    PRIVACY ACT NOTICE.--Section 6109 requires most recipients of dividend,
interest, or other payments to give taxpayer identification numbers to payers
who must report the payments to the IRS. The IRS uses the numbers for
identification purposes. Payers must be given the numbers whether or not
recipients are not required to file a tax return. Payers must generally withhold
30% (29% after December 31, 2003) of taxable interest, dividend, and certain
other payments to a payee who does not furnish a taxpayer identification number
to a payer. Certain penalties may also apply.

PENALTIES

    (1)  PENALTY FOR FAILURE TO FURNISH TAXPAYER IDENTIFICATION NUMBER.--If you
fail to furnish your taxpayer identification number to a payer, you are subject
to a penalty of $50 for each such failure unless your failure is due to
reasonable cause and not to willful neglect.

    (2)  FAILURE TO REPORT CERTAIN DIVIDEND AND INTEREST PAYMENTS.--If you fail
to include any portion of an includible payment for interest, dividends, or
patronage dividends in gross income, such failure will be treated as being due
to negligence and will be subject to a penalty of 5% on any portion of an
under-payment attributable to that failure unless there is clear and convincing
evidence to the contrary.

    (3)  CIVIL PENALTY FOR FALSE INFORMATION WITH RESPECT TO WITHHOLDING.--If
you make a false statement with no reasonable basis which results in no
imposition of backup withholding, you are subject to a penalty of $500.

    (4)  CRIMINAL PENALTY FOR FALSIFYING INFORMATION.--Falsifying certifications
or affirmations may subject you to criminal penalties including fines and/or
imprisonment.

                           FOR ADDITIONAL INFORMATION
                         CONTACT YOUR TAX CONSULTANT OR
                         THE INTERNAL REVENUE SERVICE.