On the eve of a key vote on Microsoft's OOXML format, Microsoft says it will air previously withheld information on how its software works and will license under lenient terms protocols and other intellectual property covered by its patents.

Microsoft battled through the fall last year to get OOXML accepted by the International Standards Organization as a standard. It faced criticism, coming from competitors IBM and Sun Microsystems as well as open source developers, that OOXML was tied into many proprietary Microsoft technologies. A final vote on the proposal is scheduled at a meeting in Geneva starting Feb. 25.

Last month, the European Union opened new investigations into Microsoft's alleged anti-competitive practices.

Without acknowledging these pressures, Microsoft CEO Steve Ballmer said Thursday that the company was making "a strategic shift" and was now willing to share 30,000 pages of previously undisclosed information on its Windows and desktop software. "These steps are being taken on our own," Ballmer told the New York Times Thursday.

But Microsoft's moves fall short of what open source developers say would be complete disclosure and establishing a level playing field. Microsoft, for example, promised "not to sue open source developers for development or non-commercial distribution" of software that uses Microsoft protocols.

Such an announcement, said Michael Cunningham, Red Hat's general counsel, "appears carefully crafted to foreclose competition from the open source community." Most companies, including open source companies, seek to charge a commercial fee for supporting their own code, making them still a target of a potential Microsoft patent suit. "This is simply disengenous," charged Cunningham.

"That's a severe restriction, that's not that different from what they've said in the past," said Dominic Sartorio, president of Open Solutions Alliance, a group of 23 open source-supporting companies that lobbies for greater interoperability with commercial code. Members include Iona, Hyperic, EnterpriseDB, Unisys and SourceForge.net.

Sartorio nevertheless said Microsoft's commitment to a more open mode of operation "was a small but important step" in the right direction. As part of its new openness, Microsoft officials said they will make protocols available under licensing agreements, although it acknowledges it holds patents on the protocols.

But open source developers are unlikely to be able to redistribute code under the popular open source GPL license if its derived from code covered by a Microsoft license. That's because the Microsoft license will want to maintain Microsoft's patent rights, and code that's issued under GPL loses any patent protections claimed by developers who redistribute the code.

What the Microsoft announcement does, said Sartorio, is allow open source and third party developers to create products that can interoperate with Microsoft products. Such a move was difficult in the past when connectivity and protocol information remained under wraps. An open source developer whose product knows how to connect to a Microsoft product doesn't necessarily have to be using any Microsoft IP in the process. Andrew Updegrove, a partner in the software license law firm, Gesmer Updegrove in Boston, said Microsoft committed itself to produce "new APIs ... to enable developers to plug in additional document formats" and to use those formats "as their default for saving documents." But nowhere did it commit itself to include Open Document Format, an existing international standard, as one of those that would be supported by the new APIs.

"Those people who are proponents of Microsoft's OOXML will say, 'Trust Microsoft. They know what they're doing.' But they didn't say they were going to change Word so it would support ODF out of the box," he said. The ISO's delegates are slated to soon begin considering whether they should approve OOXML as an additional international standard document format. OOXML is the default format used in the current version of Microsoft Office. The move was defeated narrowly in a nation-by-nation vote of ISO delegates last fall. Microsoft vowed to carry the fight to the Ballot Resolution Meeting in Geneva, which gets underway Monday.

It's no coincidence the Microsoft announcement comes two days before the ISO reconvenes, he said. Delegates will remain in the dark on exactly what the company will do, "while [Microsoft] reaps the maximum public relations benefit," he said.