I'm running 9.3 Beta 3. Wifi calling with AT&T Numbersync is amazing. I can initiate a call from my Mac in the Facetime App, and I can hand the call off to my iPhone. But what about in the other direction? What's the story on whether it is possible or how to do it? How cool would it be to be on the iPhone, walk into the office and transfer to the "desk phone"?