The battle for Kai-Fu Lee is heating up in the courts, as recently filed documents portray Microsoft CEO Steve Ballmer as what we know of him: fiercely competitive, and not afraid to show some, uh, enthusiasm.

The documents in question pertain to a discussion between Ballmer and Mark Lucovsky last November, when Lucovsky was considering leaving his 10-year role as an engineer at Microsoft. Ballmer purportedly picked up a chair and tossed it across the room when Lucovsky told Ballmer of his intentions to go work for Google. Ballmer then laid into Google CEO Eric Schmidt.

"I'm going to f---ing bury that guy, I have done it before, and I will do it again," the declaration quotes Ballmer. "I'm going to f---ing kill Google."

Ballmer has said that Lucovsky's recollections are "exaggerated." It's not particularly clear how Ballmer's feeling about Google are particularly relevant to the Kai-Fu Lee case, either.

What is relevant is a new e-mail presented by Microsoft that clearly shows that Google's attempt to hire Lee was coordinated, and done so with the hopes that Lee would bring plenty of benefits to the organization far beyond his role in China.

"I all but insist that we pull out all the stops and pursue him like wolves," Jonathan Rosenberg, Google's director of business development wrote of Lee. "He is an all-star and will contribute in ways that go substantially beyond China."

Of course, none of this addresses the central question regarding the enforceability of non-competes in California. It is funny to think about Ballmer tossing chairs, though.