Verizon PalmOne 650 and 2005 645ci
Paired a Treo 650 to the wife's 645 convertible without trouble. Handsfree and voice dial only. NO address book read. But it works well for what it is. Suspect BMW and Verizon will work out compatibility issues soon.
BTW, I also own a 2005 545i. I installed a charging cradle for the Motorola V710 and the phone pairs well. However, there appear to be compatibility issues between bluetooth and the dealer installed Sirius radio.
Good luck. Just pair your Treo 650 like the book in your owner's manual says. It is not hard.