[Dovecot] Not getting new mail notification

[Anand Buddhdev]

Robert Creager wrote:

Hi Robert,

> Alright.  Now running 2.6.18 kernel, and I'm getting instant
> notification, but only for Inbox.  Not for any other folders (using
> procmail filtering).  I have subscribed (Thunderbird client) to every
> folder, and if I manually go to the folder, I get notification of the
> new messages, but not until then.
> 
> Am I missing something else?

Instant notifications are made possible by the IMAP IDLE command. Your
mail client (Thunderbird), selects a folder, and then sends the IDLE
commands to the server. The server then pauses; as soon as a message is
delivered into that folder, it returns, and notifies the client of new
mail.

Unfortunately, the IMAP IDLE extension only works with one mailbox at a
time. This is a limitation in the protocol, and both Dovecot and
Thunderbird are simply following the protocol. If I remember correctly,
Thunderbird only uses IDLE for the INBOX. And while it is using IDLE,
it cannot poll the other folders for new mail (well, I suppose it could
come out of IDLE, poll all the folders, and go back to IDLE, but it
seems like an ugly hack). So you can only use one of 2 modes: either
use IDLE, and get notifications of new mail in INBOX only, or use
normals periodic polls of all your folders to get notifications of new
mail in all of them.

--
Anand