In its monthly advance notification bulletin posted earlier today, Microsoft simply said, "No new Microsoft Security Bulletins will be released on March 13, 2007."

It marks the first time in 18 months that Microsoft has not issued at least one security update in a scheduled patch rollout. Since January 2003, only three months have been sans security fixes.

Although no software will be patched this month, that doesn't mean Microsoft has nothing to do. According to security organizations, there are numerous problems still unfixed. eEye Digital Security's Zero-Day Tracker, for example, shows five vulnerabilities that have been reported to Microsoft but not patched. The SANS Institute's Internet Storm Center, meanwhile, lists nine bugs on its most recent The missing Microsoft patches chart.

However, Microsoft said it will issue several unspecified nonsecurity, high-priority updates.

Last month, Microsoft released 12 updates that fixed 20 vulnerabilities; in January, it issued four security bulletins and patched 10 bugs.