Microsoft plans to release a new version of the Windows version of its Office productivity software next year, company chairman and chief software architect Bill Gates said Tuesday.

Although many insiders had speculated that a new version of Office would come in 2006, Microsoft until Tuesday had not publicly confirmed when it would deliver the product. A 2006 release is in line with Microsoft's two- to three-year release schedules for Office. The last major version, Office 2003, arrived in late 2003.

Microsoft officials have been coy about the next Office release, which has been referred to as Office 12. Gates, in a speech at a Microsoft event for developers in Las Vegas, said the new release will offer enhancements in areas such as workflow capabilities, rights management, advanced scheduling, document sharing and business intelligence.

"Those are areas where Office has gotten richer and will in the next big release, which is coming sometime next year," Gates said.

Nailing down the date to 2006 is good, said Rob Helm, director of research at Directions on Microsoft. Still, Microsoft could provide more details to the general public on its product plans. Only a few customers who buy upgrade rights ahead of time are getting more information, under nondisclosure agreements, according Helm.

With Office 12, Microsoft is expected to release more server products designed for workgroup collaboration. Industry observers and analysts have speculated a new Excel server might be in the works, for example, but Microsoft has declined to comment. Existing server products in the Office System family include Project Server, Portal Server and Live Communications Server.

Microsoft originally planned to ship Office 12 alongside the next version of Windows, code-named Longhorn. The Office release is now likely to come before the new Windows version, which Microsoft has said will be broadly available in late 2006.