Can app running on WM5/6 PDA phone use BT headset for its own purposes?

[miamicanes]

Is it physically possible for a game or application running on a WM5/WM6 PDA phone (like the HTC Apache) to directly access and use an external bluetooth headset for its own purposes? In other words, use it for a purpose completely unrelated to making voice phone calls (like voice recognition in a video game)? If it matters or makes the task possible/easier, you can assume that the headset's only purpose in life would be to communicate with the game, that there's no need whatsoever to make it easy (or even possible) to also use the headset for making voice calls, and that the user is highly-motivated and willing/able to hand-edit the registry if necessary to make it work. Of course, painless plug & play cooperation and sharing of the headset between the phone and game would be "nice", but it's absolutely NOT a requirement in any way, shape or form.

If it CAN be done, can anyone recommend any particular part of the API to explore (or the right terms to search for)?

Example of what I'd like to do: open input stream for BT headset's microphone sound stream, receive it at the program end, decompress it (if it's compressed by the headset before sending), and do the FFTs on it.