Exhibit (a)(1)(vi)

GUIDELINES FOR CERTIFICATION OF TAXPAYER

IDENTIFICATION NUMBER ON SUBSTITUTE FORM W-9

Guidelines for Determining the Proper Identification Number to Give the Offeror—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 Offeror.

For this type of account:	Give the NAME AND SOCIAL SECURITY number of —	For this type of account:	Give the EMPLOYER IDENTIFICATION number of —
1. An individual’s account	The individual	6. Disregarded entity not owned by an individual	The owner
2. Two or more individuals (joint account)	The actual owner of the account or, if combined funds, the first individual on the account(1)	7. A valid trust, estate or pension trust	The legal entity(4)
		8. Corporation or LLC electing corporate status	The corporation
3. Custodian account of a minor (Uniform Gift to Minors Act)	The minor(2)	9. Association, club, religious, charitable, educational, or other tax-exempt organization	The organization
		10. Partnership or multi-member LLC	The partnership
4. a.The usual revocable savings trust account (grantor is also trustee)	The grantor-trustee(1)	11. A broker or registered nominee	The broker or nominee
b. So-called trust account that is not a legal or valid trust under state law	The actual owner(1)	12. Account with the 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	The public entity
5.      Sole proprietorship or disregarded entity owned by an individual	The owner(3)

(1) List first and circle the name of the person whose number you furnish.

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

(3) You must show your individual name, but you may also enter your business or “doing business as” name. You may use either your social security number or employer identification number (if you have one) but the IRS encourages you to use your social security number.

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

NOTE: If no name is circled when more than one name is listed, the number will be considered to be that of the first name listed.

Purpose of Form

A person who is required to file an information return with the IRS must obtain the correct taxpayer identification number (TIN) to report, for example, income paid to you, real estate transaction, mortgage interest you paid, acquisition or abandonment of secured property, cancellation of debt, or contributions you made to an IRA.

Use Form W-9 only if you are a U.S. person (including a resident alien), to provide your correct TIN to the person requesting it and, when applicable, to:

1. Certify that the TIN you are giving is correct (or you are waiting for a number to be issued);

2. Certify that you are not subject to backup withholding; or

3. Claim exemption form backup withholding if you are a U.S. exempt payee.

Definition of a U.S. Person

For federal tax purposes, you are considered a U.S. person if you are:

1. An individual who is a U.S. citizen or U.S. resident alien,

2. A partnership, corporation, company, or association created or organized in the United States or under the laws of the United States,

3. An estate (other than a foreign estate), or

4. A domestic trust (as defined in Treasury regulations section 300.7701-7.

Foreign Person

If you are a foreign person, do not use Form W-9. Instead, use the appropriate Form W-8.

How to Obtain a TIN

If you don’t have a taxpayer identification number or you don’t know your number, obtain Form SS-5, Application for a Social Security Number Card, or Form SS-4, Application for Employer Identification Number, at the local office of the Social Security Administration or the Internal Revenue Service (“IRS”) and apply for a number. If you do not have a TIN and have already applied for a TIN or intend to apply for one soon, write “Applied for” in the space for the TIN on the Substitute W-9. Sign, date, and return the form to the Payer. Section references in these Guidelines refer to sections in the Internal Revenue Code of 1986, as amended.

Payees Exempt from Backup Withholding

Payees exempt from backup withholding on all payments include the following:

• An organization exempt from tax under section 501(a), any IRA, or a custodial account under section 403(b)(7) if the account satisfies the requirements of Section 401(f)(2).

• The United States or any of its agencies or instrumentalities.

• A state, the District of Columbia, a possession of the United States, or any of their political subdivisions or instrumentalities.

• A foreign government or any of its political subdivisions, agencies, or instrumentalities.

• An international organization or any of its agencies or instrumentalities.

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Other payees that may be exempt from backup withholding include:

• A corporation.

• A foreign central bank of issue.

• A dealer in securities or commodities required to register in the United States, the District of Columbia, or a possession of the United States.

• A futures commission merchant registered with the Commodity Futures Trading Commission.

• A real estate investment trust.

• An entity registered at all times during the tax year under the Investment Company Act of 1940.

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

• A financial institution.

• A middleman known in the investment community as a nominee or custodian.

• A trust exempt from tax under section 664 or described in section 4947.

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 United States and that have at least one nonresident alien partner.

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

• Payments made by certain foreign organizations.

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 of business and you have not provided your correct taxpayer identification number to the payer.

• Payments described in section 6049(b)(5) to nonresident aliens.

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

• Payments made by certain foreign organizations.

Exempt payees described above should file Substitute Form W-9 to avoid possible erroneous backup withholding. FURNISH YOUR TAXPAYER IDENTIFICATION NUMBER, CHECK THE EXEMPT BOX IN PART III, SIGN AND DATE THE FORM, AND RETURN IT TO THE PAYER. IF YOU ARE A NON-RESIDENT ALIEN OF A FOREIGN ENTITY NOT SUBJECT TO BACKUP WITHHOLDING, FILE WITH PAYER A COMPLETE FORM W-8.

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, 6041A(a), 6045 and 6050A.

Privacy Act Notice.—Section 6109 requires most recipients of dividend, interest or other payments to give their correct taxpayer identification numbers to payers who must report the payments to the IRS. The IRS uses the numbers for identification purposes and to help verify the accuracy of tax returns. Payers must be given the numbers whether or not recipients are required to file tax returns. Payers must generally withhold 28% (or such

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other rate specified by the Internal Revenue Code) 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 correct 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) 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.

(3) Criminal Penalty for Falsifying Information.—Willfully falsifying certifications or affirmations may subject you to criminal penalties including fines and/or imprisonment.

(4) Misuse of Taxpayer Identification Numbers.—If the requester discloses or uses taxpayer identification numbers in violation of U.S. federal law, the requester may be subject to civil and criminal penalties.

FOR ADDITIONAL INFORMATION CONTACT YOUR TAX

CONSULTANT OR THE INTERNAL REVENUE SERVICE.

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