Well, i have seen posts about bluetooth problems with the CDMA iPhone 4 and bluetooth on other forums, but i cannot find anything here with just general issues with connecting multiple times to a bluetooth device
The problem that i have and have seen others have, including my dad, is that after pairing my iPhone with my kenwood stereo, it will work for that session, and might connect automatically the next time, but after 2 times it generally wont work automatically. If i try to connect manually, either from the phone or from the kenwood deck, it wont connect until i turn off bluetooth on the phone and turn it back on, and then manually connect from the iphone.
The same problem happens with my dad's iphone on my stereo, as well as his Ford Sync system with bluetooth.
I have the same issue with my Kenwood on my AT&T phone, have had it for a while. I sometimes have to pop the faceplate on the stereo to get it to connect. Sometimes it just works flawlessly and other times I have to fight with one or the other.