[Dovecot] IMAP subscriptions - how, for what and why?

[Tom Alsberg]

Again, not a Dovecot issua - but can someone clarify better what IMAP
subscriptions (SUBSCRIBE/UNSUBSCRIBE/LSUB) are and what they are used
for?

I've seen a few times in Microsoft mail clients, the options to
subscribe to folders and to "show only subscribed folders".  I haven't
played much with them, though.  But what's the actual point?  Except
for being returned in the list of LSUB, what else changes when doing a
SUBSCRIBE to a mailbox?

Are subscriptions supposed to be remembered by the server outside of
the context of a session (so a client that connects to the server at
some point and authenticates will already see in LSUB what a possibly
other client has subscribed to in a previous session)?

  Clarifications appreciated, regards,
  -- Tom

-- 
  Tom Alsberg - hacker (being the best description fitting this space)
  Web page:	http://www.cs.huji.ac.il/~alsbergt/
DISCLAIMER:  The above message does not even necessarily represent what
my fingers have typed on the keyboard, save anything further.