I believe that autoconfig should provide a way to set the special imap folder like the Sent Mail, Draft, Junk,... because this is something very annoying and difficult to set for a new user. => So I create the corresponding bug: https://bugzilla.mozilla.org/show_bug.cgi?id=475139
Similarly, at one point I had an email discussion with mscott about having the ability of the ISP files to list a Junk Mail header -- for instance, Yahoo uses "X-YahooFilteredBulk" to indicate a message caught by their antispam software --Miles