[Dovecot] Mailbox aliases

[Timo Sirainen]

I've been wondering about ways to handle all the various different Sent/Sent Messages/Sent Items/etc mailboxes that different clients create and if there could be a way to make them work at least somewhat better. I'm mainly thinking about ISP-like installations where users are using tons of different clients and there's no way to get everyone configured properly. Of course the eventual solution is hopefully that all the clients will support SPECIAL-USE extension, but while waiting for that maybe mailbox aliases could help some.

So one possibility would be to force autocreation of wanted specific mailbox names, and create aliases for the other commonly used mailboxes. The main difference here for the current behavior is that all of the mailboxes would contain the same mails, instead of different mails going to different mailboxes with different clients. So for example:

..
mailbox Sent {
  auto = create
  special_use = \Sent
}
mailbox "Sent Messages" {
  special_use = \Sent
  alias_for = Sent
}
..

If "Sent Messages" doesn't exist:
 - DELETE Sent works as usual
 - RENAME Sent works as usual

If "Sent Messages" is created:
 - it's symlinked to Sent
 - DELETE "Sent messages" deletes the symlink, not the contents
 - RENAME "Sent messages" isn't allowed
 - DELETE/RENAME Sent fails with message: Delete/Rename for Sent not allowed before "Sent Messages" is deleted.

Thoughts?

The main disadvantage is that clients would still see two different mailboxes, and some would download contents from both of them.

I was thinking about creating some wiki page which could list the best working configurations and also a client list, which would specify if it supports SPECIAL-USE and what the default mailbox names it uses are.