Or how about either:
1. A separate, restricted "Known Bugs" forum whereby a moderator/WG staff would move a topic from the V6 forum to the Known Bugs forum when the reported problem was verified as being a bug. No one would be allowed to post directly to the Known Bugs forum. This would put all the known bug topics in one place.
2. A new topic symbol (perhaps a little bug?) that a moderator/WG staff would place/change next to a topic when it becomes a confirmed bug. Then one could elect to display only the topics in the V6 forum that were known bugs.