In a splashy announcement last week, Microsoft touted new efforts to improve the interoperability of its key software products with open source projects and products from other vendors.

Some in the open source and free software communities, however, were underwhelmed. Asked about Microsoft's move, several said the company's new "interoperability principles" are more talk than substance.

Under the initiative, Microsoft is publicly releasing more than 30,000 pages of documentation for Windows protocols and APIs -- information previously available only under special licenses -- as one of several changes in how it deals with open-source developers and software rivals. Calling the four steps "interoperability principles," Microsoft promised to make it easier and cheaper for developers to create software that works smoothly with its highest-profile and most-current products

The list of products includes Windows Vista, Windows Server 2008, SQL Server 2008, Office 2007, Exchange Server 2007 and Office SharePoint Server 2007, as well as all future versions of those programs. The company also plans to promote data portability, enhance its support of industry standards and work more closely with the open-source community. Under the initiative, Microsoft protocols covered by patents will be freely available to open-source developers for "noncommercial" purposes, and the company agreed not to sue anyone who use or distribute protocol implementations in noncommercial instances. Companies would still have to license Microsoft's patents, however, if they use them in commercially distributed software.

Therein lies the rub, said Peter Brown, executive director of the Boston-based Free Software Foundation.

"They have made pledges before," Brown said. "This is a clear attempt to still keep free software and the work under the GPL (General Public License) away from the Microsoft platform. Our community is already well aware that the offer is pretty useless because of the non-commercial requirement. No one will do this in the free software community."

By adopting such language, Brown said, Microsoft is essentially telling free software developers to "stay in your basement" and don't come out with useful code. "It's great for free software developers as long as they don't interact with the real world" and create code for commercial software.

"I continue to be wary of Microsoft's stance toward free software," Brown said, adding that the new principles appear "to be a show for the European Union," which continues to review antitrust actions against the company.

"I'm pretty unimpressed," Brown said. "It's business as usual for Microsoft. If you market [software created under the new rules] then you'd have to pay royalties to Microsoft, which isn't done under the GPL and free software. It's a fake offer in many ways as far as our community is concerned. They would need to make all the implementations free from any conditions."

Michael Cunningham, executive vice president and general counsel of Linux vendor Red Hat Inc. said in a statement that "we've heard similar announcements before, almost always strategically timed for other effect. Red Hat regards this most recent announcement with a healthy dose of skepticism."

If Microsoft were really committed to fostering interoperability, he said, the company would "commit to open standards, rather than pushing forward its proprietary, Windows-based formats for document processing, OOXML.

"Microsoft should embrace the existing ISO-approved, cross-platform industry standard for document processing, Open Document Format (ODF) at the International Standards Organization's meeting next week in Geneva," Cunningham said. "Microsoft, please demonstrate implementation of an existing international open standard now rather than make press announcements about intentions of future standards support."

The company should also "commit to interoperability with open source" rather than "offering a patent license for its protocol information on the basis of licensing arrangements it knows are incompatible with the GPL -- the world's most widely used open source software license."

In addition, Cunningham said, Microsoft should "commit to competition on a level playing field.

"Microsoft's announcement...appears carefully crafted to foreclose competition from the open source community," he stated. "How else can you explain a 'promise not to sue open source developers' as long as they develop and distribute only 'non-commercial' implementations of interoperable products? This is simply disingenuous."