What's behind Microsoft's open-source deals?

Microsoft views its string of deals with Linux vendors--the latest being Linspire, announced this week--as part of a broader company wide push to improve interoperability.

That's the word from Tom Robertson, Microsoft's general manager of interoperability and standards, and Jean Paoli, its general manager of interoperability and XML architecture (and a co-creator of the original XML standard). On Friday, the pair published an open letter, again calling on the industry to give the Office Open XML document format a fair shake as a standard.

Technology and legal pacts with open-source companies serve dual purposes, they said in an interview Thursday with CNET News.com.

What's behind Microsoft's open-source deals?