lmtp read timeout

[Matt Bernstein]

At 22:27 +0100 Lindner wrote:

>   1.  -> lmtp read timeout <- What problem is meant ? Postfix is
>      writing to the unix socket but nobody reads from the socket or
>      Cyrus is reading from the socket but nobody is writing to it ?

I've seen this with Exim. Exim sends the DATA phase and never hears back
from lmtpd. It only happens for specific recipients, so the only effect is
that mail delivery is stalled for some users. Restarting "master" seems to
fix it: a bit heavy, but fine for most people, as most IMAP clients just
re-authenticate. Fussy clients (like mine ;) tell you something's awry.