Microsoft said Thursday it will for the first time license protocols in its instant messaging, e-mail, and collaboration technologies to rivals so that they could create programs that work smoothly with the company's server software.

The move could be seen as a bid by the Redmond, Wash. software developer to placate antitrust regulators in Europe, where competitors continue to file complaints with the European Union's watchdog agency. Just last week, IBM, Sun, and other rivals that make up the European Committee for Interoperable Standards sent a letter to the EU's Competition Commission charging that Windows Vista violates EU antitrust law.

Microsoft itself was more oblique in explaining its reasons for releasing the protocols. "In terms of us being proactive, making these three protocols available is part of the process of listening to our customers, partners, and competitors," said spokesman Guy Esnouf in an e-mail. "This process will continue and accelerate so we understand more of their interop[erability] requirements and look at ways that we can address any areas where they feel they do not have the access they need today."

Two of the three protocols are available for licensing immediately, while the third will debut in April.

The Outlook-Exchange Transport Protocol, available now, will allow rival e-mail server software to use the Outlook-Exchange Transport Protocol, the messaging standard that Outlook 2007 uses to communicate with Microsoft's own Exchange 2007 server.

Also ready immediately is what Microsoft's calling "Office Collaboration Server Licensing Program," which provides documentation and IP rights so competitors can add Office 2007 document management features to their collaboration server software. In the Microsoft ecosystem, Office 2007 connects with Microsoft Office SharePoint Server 2007 for such chores as publishing workgroup Excel 2007 spreadsheets. "The protocol will mean better working with other non-Windows servers," Esnouf said.

In two months, Microsoft will offer a third protocol, "Live Communications Server 2005 Protocol Extensions," so competitors can add Microsoft-based instant messaging and presence indicators, such as "online" or "busy" to their applications.

Microsoft has repeatedly tangled with the European Union's antitrust agency over its responsibilities under a 2004 ruling that ordered the American company to pay a $613 million fine and document a number of Windows server protocols. In July, 2006, the Competition Commission fined Microsoft an additional $357 million for not wrapping up the protocol documentation project on schedule.

Although Microsoft met the commission's November 2006 final deadline in submitting the revised technical documentation, the antitrust agency has not yet made a final decision whether the company has met all its obligations. A new 3-million-euro-per-day ($3.9 million) fine could be backdated to July 31, 2006 if at some point the commission decides that the documentation is lacking.

An EU spokesman could not be reached for comment on the Microsoft protocol licensing.