[Dovecot] Timeouts connecting via POP3

I'm experiencing timeouts from time to time from both Mac Mail and Outlook when connecting to my server. I originally suspected that it might be process # related, so I increased the auth & login process counts but that hasn't seemed to make a difference.

I'm running 1.0rc10 which came with my DirectAdmin control panel. I'm wondering if this problem is known and was fixed in a later release? I'm waiting for instructions from the DirectAdmin folks on building a new version in case they do something special.

Any ideas?

Thanks!