I also agree with Andre, specific enhancement requests belong in bugzilla while things that are not very clear cut should go through brainstorm first.

Good example :-) There really isn't much to brainstorm about this - it's a specific enhancement request about a well understood feature that nearly every other IMAP client has, so it should be (is actually) in bugzilla. The proposed "solutions" (arguing about who implements it or suggesting the use of alternative clients) make this all the more evident IMHO.

On the other hand, here's an example of something much more fuzzy and complex (that I would have submitted to brainstorm if I had even a single idea about how to approach it that didn't suck :-/ ).