Office 2003 hit the retail shelves in late October, although volume buyers could get it a month earlier.
The release also will include fixes and security bolstering as part of the company's continued security push, code-named Springboard, the sources said.
"This is a date-driven release," an insider confirmed. Some pointed out that the rush to finalize code appears to run counter to the company's push to build in quality and security up front and not ship products until they are solid.
Officially, Microsoft is circumspect on the subject. The service pack "is still in the early development stages, so anything we say about it would only be speculation right now, as a lot can change during the development process," said Dan Leach, lead product manager of the Information Worker Product Management Group, through a spokeswoman. "One thing we can say is that, thanks to new technologies like Watson, and feedback from over 600,000 beta testers, the newly launched Office System represents the most stable, reliable and secure version of Office Microsoft has ever produced."
Microsoft has acknowledged that Watson and new tools including Service Quality Monitor (SQM) are key in the development of the Longhorn Office release, also known as Office 12.