@gruber No, it doesn't work on a list of messages. IIRC this technique was the old way, before Mail's "move" command worked properly.
@gruber For SpamSieve I changed it to set the mailbox property of each message.
@pilky Doesn't sound so bad to me; Xcode 4 can't sort alphabetically!
@FogBugz is down, and so is www.fogcreek.com!
@jimcorreia Yeah, I too got a big scheme surprise when I didn't keep a certain file under version control.