IMAP crashing on message move

[Jaime]

	When trying to move a message from my INBOX folder to another  
folder, I usually (4 out of 5?) find that the imapd process has  
crashed.  SquirrelMail is nice enough to tell me this:

ERROR: Connection dropped by IMAP server.
Query: COPY 18238,18255 "mail/Trash"

	Looking in /var/log/messages, I find lines like this:

Jul 11 21:28:47 atlas kernel: pid 81702 (imapd), uid 1001: exited on  
signal 11

	This is using FreeBSD 6.1-Stable built from sources a few days ago  
and the ports for imap-uw, cclient, squirrelmail, php5-imap, etc.  
built from ports updated yesterday afternoon.  I've seen the above  
error in /var/log/messages for a few other UIDs, too.  So I know its  
not just me.

	This is a new server.  The old server was working OK with these same  
files in /home (I moved the data over using a tar czpf archive.tar.gz  
-C /home . command.) and FreeBSD 5.x and imap-uw, et. al. built from  
ports as well.  The most significant change that I can find is the  
move from php4 to php5, but that shouldn't cause the imapd process to  
fail, right?

	Any thoughts, tips, advice, etc. is greatly appreciated.

							Jaime