Microsoft is pushing customers to upgrade to the latest service packs for Office, but not for the usual security and performance reasons.

Ten days ago, Microsoft began notifying its volume-license customers that they should upgrade to the latest service packs for Office in order to comply with a patent-ruling against Microsoft.

"It was recently decided in a court of law that certain portions of code found in Microsoft Office Professional Edition 2003, Microsoft Office Access 2003, Microsoft Office XP Professional and Microsoft Access 2002 infringe a third-party patent. As a result, Microsoft must make available a revised version of these products with the allegedly infringing code replaced," according to the note.

The customer note did not offer details regarding the specific legal reasons for the patch push. But a public relations official with the company said that the updates were required as part of a U.S. federal court ruling in June 2005 that found Microsoft guilty of infringing on a Guatamalan investor's 1994 patent on technology linking Microsoft Access and Excel.

The court ordered Microsoft to pay the inventor, Carlos Armando Amado, $8.9 million in damages. Microsoft is appealing that ruling.

"We're appealing the decision, but in the meantime requiring these changes through the recent service pack upgrade," the Microsoft PR manager, Jack Evans, confirmed.

Microsoft advised Office Professional Edition 2003 and Office Access 2003 users to install Office 2003 Service Pack 2 for all current and future deployments. And it advised Office XP Professional and Access 2002 users to upgrade to the Office XP SP3 Patch for all current and future deployments.

Microsoft suggested customers obtain these updates by downloading them directly from the Office downloads Web site or by contacting their resellers.