[Dovecot] Apple Mail and too many open files?

Hello,

For two days in a row, I've noticed that my dovecot server (hosted on
a PowerMac running OS X) has stopped working, with a bunch of error
messages in /var/log/mail.log like: May 24 07:31:10 top dovecot: pipe() failed: Too many open files

To solve this, I have to kill -9 dovecot and the (many) imap
processes running.

The only client accessing the server is a machine running Apple Mail.
I tried to increase the limit in the number of files (I did a
"launchctl limit maxfiles 1024 unlimited", but the problem still
happened.

Is this a known problem? Should I allow still more files?

Thanks,

Alan

-- Alan Schmitt http://alan.petitepomme.net/

The hacker: someone who figured things out and made something cool
happen. .O. ..O OOO