Ivo Jansch has been attending the php|tek 2008 conference this past week and some things have come to light about the rumors between Zend and Microsoft. One of his latest posts sheds some light on how Microsoft responded (as answered by Joe Stagner)
Joe had an interesting presentation, he kept it short and to the point, and had the majority of his time dedicated to Q&A. Naturally, being in a PHP audience, the questions were about Yahoo, Zend, Microsoft's open source policies.
Obviously, questions were asked about two things - the Zend buyout and whether or not they have stopped talks with Yahoo. The answer to the first was a "no, we're not doing that" and the second was a more vague "we're not done talking to them" sort of answer. Another discussion included Microsoft's contributions to the Zend Core - how they're handled and if they're contributed back.