Microsoft continued to release formerly closely held application protocol documentation Tuesday, posting 14,000 pages of information for Microsoft Office 2007, SharePoint Server 2007, and Exchange Server 2007 at MSDN, a Web site for developers.

The information released includes protocols that allow Exchange Server to communicate with Outlook and those used by Office and SharePoint to communicate with each other and with other Microsoft server products. Most of this information was available previously only under a Trade Secret license made available only to select partners.

"Microsoft is pleased to announce another step toward putting our interoperability principles into action," Tom Robertson, Microsoft's general manager of interoperability and standards, said in a statement. Microsoft announced a set of four interoperability principles in February, including the release of protocol documentation, which it says will lead to a more "open" Microsoft. In separate antitrust cases, the United States and the European Union had long sought for Microsoft to release protocol documents, but trends like Linux and Web 2.0 are increasingly forcing Microsoft's hand.

The protocol documentation released Tuesday is only preliminary; the company has said that more complete documentation for these products will be available by June. Between now and then, Microsoft will collect information from developers whose feedback will help determine the final shape of the documentation. Microsoft's created a number of forums to encourage feedback.

Despite Microsoft's pledged openness, there's still a devil in the details with the release of this information. Microsoft's protocol documentation, which includes 30,000 pages of Windows Server and Windows client documentation already released, is free to anyone to download, but protocols Microsoft deems covered by a patent -- patent maps are being made available -- can only be implemented freely by noncommercial open source developers. Commercial developers and enterprises will have to pay Microsoft royalties for their use. For that reason, Gartner has warned companies of the risks of freely implementing these protocols.

Formal terms of protocol patent licensing hasn't yet been made available and won't be until June, but Microsoft has licensed Windows Server protocols patent for prepaid royalties of $10,000 plus additional royalty rates of anywhere between 40 cents and $20 per unit of software sold, or between 0.10% and 0.40% of revenue made from the products in question per protocol, depending on the protocol used.

In addition to the protocol documentation already released, Microsoft has said it will release SQL Server documentation by June and other information going forward. "No one said that Microsoft's efforts in this area would stop with the release of 30,000 pages of technical documentation," Robertson said in a recent interview.