[Dovecot] Problems with dovecot 1.0rc5 + MySQL 5.0.24

Hi all,

I'm having an intermittent problem logging users in through a webmail client (RoundCube). My maillog reports this:

auth(default): vmysql: sql error[3]: MySQL server has gone away imap-login: Disconnected: user=<sales@coppersinkdepot.com>, method=PLAIN, rip=127.0.0.1, lip=127.0.0.1, secured

The MySQL server hasn't gone anywhere, I can log into it fine and other apps report no problems with it.

Restarting Dovecot fixes this issue, but it'll just happen again later.

I'm on OpenBSD 3.9 using vpopmail.

I've looked through the mailing list archives but can't find any info on this specific problem.

Any ideas?