[Dovecot] Mailbox locking problem with iphone and POP3

[Mark Hedges]

On Fri, 7 Aug 2009, Timo Sirainen wrote:
> On Mon, 2009-08-03 at 10:47 -0500, Bill Dunn - VCI
> Internet Services wrote:
> > I have a problem I can't seem to fix. I have dovecot
> > configured to do POP3 with plain text authentication
> > using a MySQL database. I am using Dovecot 1.0.7 with
> > fcntl locking.
>
> So you're using mbox format?
>
> >     My problem has been when an iPhone/iPod checks
> > email. The iPhone/iPod doesn't disconnect with a TCP FIN
> > packet and it leaves the mailbox in a locked state and
> > prevents the user's desktop from checking email. I have
> > tried changing the file locking method and other config
> > file options without any luck.
>
> Do you have pop3_lock_session=no?

This is an old thread, but I'm having the same problem.

pop3_lock_session=no

The iphone checks mail, and disconnects uncleanly.  Then
there is a delivery attempt.  I have procmail logging on,
and procmail sits there trying to lock the spool file until
the timeout is reached and it overrides the lock.

This causes the error "timeout waiting for input from local
during Draining Input" in sendmail, which is a generic error
that means the delivery process or subprocess generated
warning output on stderr.

(Incidentally does anyone know how to get access to
procmail's stderr output?)

I've tried a number of different lock combinations.  Nothing
seems to help.  Mail eventually gets delivered, though, so
it's not a huge deal at the moment.  I don't know how it
behaves when the iphone tries to connect again while the box
is still locked.

Mark