Exhibit 99.1

CERTIFICATION OF CHIEF EXECUTIVE OFFICER AND CHIEF FINANCIAL OFFICER
PURSUANT TO
18 U.S.C. SECTION 1350,
AS ADOPTED PURSUANT TO
SECTION 906 OF THE SARBANES-OXLEY ACT OF 2002

I, Bruce L. Claflin, certify, pursuant to 18 U.S.C. Section 1350, as adopted pursuant to Section 906 of the Sarbanes-Oxley Act of 2002, that the Quarterly Report of 3Com Corporation on Form 10-Q for the fiscal quarter ended February 28, 2003 fully complies with the requirements of Section 13(a) or 15(d) of the Securities Exchange Act of 1934 and that information contained in such Quarterly Report on Form 10-Q fairly presents in all material respects the financial condition and results of operations of 3Com Corporation.

By:	/s/ Bruce L. Claflin
Name:		Bruce L. Claflin
Title:		President and Chief Executive Officer

I, Mark Slaven, certify, pursuant to 18 U.S.C. Section 1350, as adopted pursuant to Section 906 of the Sarbanes-Oxley Act of 2002, that the Quarterly Report of 3Com Corporation on Form 10-Q for the fiscal quarter ended February 28, 2003  fully complies with the requirements of Section 13(a) or 15(d) of the Securities Exchange Act of 1934 and that information contained in such Quarterly Report on Form 10-Q fairly presents in all material respects the financial condition and results of operations of 3Com Corporation.

By:	/s/ Mark Slaven
Name:		Mark Slaven
Title:		Executive Vice President, Finance, and Chief Financial Officer