^^^ I removed the factory Premium rSAP Kit (part number 730) and replaced it with the 729 Standard Bluetooth (with uses the much more widely supported Hands Free Profile).
I use this kit a Blackberry 8310 (work phone) or iPhone 3GS.
Have also successfully tried a couple of HTC's, the Blackberry Storm, Pearl and Bold plus a few Nokia's like the 5200, N95, N97.