The good news is that there is a long, obnoxious work around. You can find that in the "old" forum. It does work...I've tried it.
The bad news is that the Blackberry (I have an 8830 with Verizon) is not really suited for streaming audio. It really takes a toll on your battery. You'll need to have a charger or spare battery with you if you plan to do any serious streaming.