The latest IMAP4rev1 draft specifies that UNSEEN reply is required after SELECT and EXAMINE, but it doesn't say what to do when there are no unseen messages.
Simply not sending it doesn't seem a good idea, since client would have to issue a SEARCH UNSEEN only to find out there's none. Maybe a new [NO-UNSEEN] tag if there's none? -- ----------------------------------------------------------------- For information about this mailing list, and its archives, see: http://www.washington.edu/imap/imap-list.html -----------------------------------------------------------------
