On my Blackberry 8800,
I was unable to get Bluetooth to work for more than an hour or so. Thereafter, everything Bluetooth was goofy: scans to pair would freeze, the blue light on the phone would still blink after I disabled Bluetooth, etc.
Fortunately, I was able to find this post, because I removed the group and it immediately worked. No other changes / downloads were needed.
I had added one group, my family members so I could broadcast messages to them all. I really like and use that feature; I hope there is a fix for this bug. I'm presuming it's RIM that needs to address this.
BTW, this forum needs to change it's search feature. If you try to search for "Java.lang.ClassCastException" it reports that this string is too long to search for! I was only able to find this using google's handy "site" search by doing a google search on:
"Java.lang.ClassCastException" site:
www.blackberryforums.com