It has long been talked about: Microsoft IntelliMouse for Bluetooth and Mac OS X.
I can confirm 2 things for you:
1) the IntelliMouse DOES work with Mac OS X. And its dongle works in Mac OS X too. However, since the dongle is Bluetooth 2.0, it only works in Tiger, not Panther. And it's right, you don't need special drivers, Mac recognize it.
2) The dongle does NOT support headset profile. Hardware wise not. While in Windows, the MS driver does not tell you if this is a driver problem or a hardware issue. Mac tells you right a way. "The hardware does NOT support headset profile". So save you some time, don't bother download wincomm etc.
One good thing about Mac is it comes with generic drivers for many devices. Nowadays, most brand-named products are actually OEM of some very generic stuff and you know Microsoft is not a chip maker, so. . .
Yeah, sure enough, once you connect your MS Bluetooth 2.0 dongle for the mouse to Mac OS X Tiger (either intel or PowerPC) it is recognized and started. You can pair the mouse easily.
When you try to add device and choose headset, you will be told the hardware does not support this profile.
So, kudu to the Mac! You can use Microfot IntelliMouse for Bluetooth even though Microsoft says "support Windows ONLY". Yeah! Who trust Microsoft! Well holdon on that statement, Microsoft said the dongle does not support headset, and it is true, it does not!.