Sure - it was one of these.Do you have details/link for the bluetooth module you're using pls mate? I think I have the same, single-cd Blaupunkt unit and was under the impression BT could only be added to the 6-disc changer models
Cheers!

Bluetooth Music Hands free MP3 adapter for BMW E46 Z3 Business radio | eBay
Find many great new & used options and get the best deals for Bluetooth Music Hands free MP3 adapter for BMW E46 Z3 Business radio at the best online prices at eBay! Free delivery for many products!
www.ebay.co.uk