Must be an old module. You can change it for about £200 off eBay. Not sure if you can check version info without using VCDS or looking on module itself (in foam wrapper under drivers seat). If you can post the model number of your module, then I can help further.
Remote Sim Access Profile (rSAP) is not that common on smartpones, they all use Hands Free Profile (HFP) for voice and phone book. rSAP also does SMS and actually is a mobile phone in it's own right, so just uses the phone to access the SIM card, phonebook and network. That's the drawback - a smartphone would then be unable to be smart while connected, as both car and phone can't access the SIM at the same time. Maybe that's why they don't support it?
If your network let's you have two SIMs connected at same time (some do), then you could use and old Nokia hidden in the back of your desk drawer as a car phone? A bit of a muddle, mind you!
@Doc: Agree that rSAP (Premium) is awesome, but the A2DP means newer phones do work well, too. Wife's crappy Nokia gets SMS and brilliant signal. Come on Apple!