On Bimmerforums someone says that the problem was fixed when the software was updated, but also says that it might return in a few months...
http://forums.bimmerforums.com/forum/showpost.php?p=10216765&postcount=5But nothing more than you found on e60 forums (found the thread you were in), hope you'll get your car back fixed and well...
Sorry, dunno how to help on this one, I think this is where the dealer comes in... Good Luck!