Microsoft\u00a0is limiting testing of the next release of its Office productivity software to versions of the Windows operating system dating back only to Windows 2000, which could mean the final version of the software won't support older systems.The company would not confirm or deny reports that the lack of testing for earlier systems means that Office 11 won't work on previous versions of the operating system when it is released generally. Those include Windows ME (Millennium Edition), Windows NT, Windows 98, Windows 98 SE (Special Edition) and Windows 95."At this point we're still doing testing," a company spokeswoman said Tuesday.BetaNews, a Web site devoted to information about products under development, reported Tuesday that Microsoft disclosed its plans in a message board for Office 11 beta testers, citing a posting attributed to a Microsoft developer."There were a number of reasons for removing support for Windows 9x. As a number of you have noted, Windows 98 and 98 SE are getting a bit old now. It also relates heavily to the push to improve security in our products. Windows 9x is inherently insecure," the posting read, according to BetaNews."We understand that this decision won't be popular among all of our customers, but it allows us to create a better and more stable product," it continued.With a few thousand beta testers currently using and debugging the early code, Microsoft said it is too early to comment on the exact system requirements for the final product. It continues to gather feedback from testers and it has not made any final decisions on support, the spokeswoman said.Office 11 is expected to undergo a wider\u00a0beta test\u00a0in the next few months and be released in its final version in mid-2003 with new features that take advantage of the open standard XML.The lack of support for older operating systems wouldn't be a first for Microsoft. The Redmond, Washington, company has dropped support for past versions of its operating system with some new software releases. For example, Office XP can't be installed on PCs running Windows 95, according to Paul DeGroot, an analyst with Directions on Microsoft , in Kirkland, Washington.For one, new features expected to make it into Office 11 might require more advanced technology and security than what's available in older versions of Windows. "To some extent, Microsoft may just be being fairly realistic about the market. They've got a product that might not run well on the typical Windows 98 machine," DeGroot said.He also speculated that Microsoft's decision could be an effort to drive more customers to upgrade to its most recent operating system release, a goal that has led to the company's new licensing model, which requires customers to run current versions of Windows."Certainly there's not a lot of incentive for Microsoft to do that (backward compatibility). They want you to upgrade," DeGroot said.