Microsoft Extends Exchange 5.0, 5.5 Support To Patch Critical BugMicrosoft Extends Exchange 5.0, 5.5 Support To Patch Critical Bug

Microsoft formalized a change in its support policies Tuesday as it broke with past practice of not supplying patches after a product's put out to pasture.

Previously, support for a product ended at the end of a calendar quarter: Dec. 31, March 31, June 30, Sept. 30. But those dates are just days before the second Tuesday of the month following, when the Redmond, Wash.-based developer regularly releases patches.

From now on, the company will instead wrap up support with the next monthly security update release cycle. Products that would have had support dropped as of Dec. 31, 2005, for example, were still covered in the Tuesday, Jan. 10, 2006, security updates.

"We changed the end of support dates to map to the monthly security update release cycle so our customers can take advantage of the latest security updates," said Ines Vargas, group manager for Microsoft's support lifecycle program, in a statement. "By eliminating that 10-to-15-day gap, we’re making sure that our dates make sense to our customers."

The change most impacts Exchange 5.0 and 5.5 users, who were to be cut off from all support -- including critical security updates -- as of the end of 2005, but who received a patch for a critical vulnerability Tuesday.

"This is a very good thing for our customers in terms of our Trustworthy Computing initiative," Vargas added.

It may have more to do with the severity of the vulnerability than with any Microsoft initiative.

"This bug has massive financial implications," claimed Mark Litchfield, co-founder and director of NGS Software, the U.K.-based security company credited with discovering the flaw. "If enterprises didn't patch yesterday, they'd better be patching today," he added.

The vulnerability affects older editions of Microsoft Exchange, from the now-obsolete 5.0 and 5.5 through Exchange 2000 Server. Microsoft Exchange Server 2003, however, is immune.

More information about the fixes for Exchange are available in Microsoft's MS06-003 security bulletin.