Hang on send with attachment, messages go but no copy in IMAP Sent

[fonce]

Sorry for the confusing title, I was trying to get it all in there without being too long.  I'm running RC 0.2.1, connecting to IMAP (dovecot 1.0rc2), sending via Postfix (2.2.11) and am having absolutely no problems sending mail that has no attachments.  A copy goes right into Sent and the message sends almost instantaneously.

However, if I attempt to send a message with an attachment the message will send and get to its destination (I've tried a bunch) just fine, including to self, but RC will hang with the "Sending message..." box displayed.  This causes the Sent folder to hang when I restart the browser and then log back in.  The same issue applies for the Drafts folder in that I can save a draft that doesn't contain an attachment but not one that does.  After a considerable period (a few minutes) the session times out (I'm presuming) and lets me back into the afflicted folder.  No copy is ever saved, though, despite its successful send.

I'm relatively sure it's not a php.ini issue as sending attachments works just fine.  In main.inc.php I changed sent_mbox to blank and it sends instantly, so it really appears this is an issue with saving a message containing attachments to an IMAP folder.

I've spent the last three days poring over tons of posts and maillist entries about this but have found no solution to this specific issue.  Any ideas?

Edit: checked my RC, IMAP, and Postfix logs and found nothing from anywhere near the time of testing.

[fonce]

Nobody else has experienced this issue?

[fonce]

This issue no longer exists with more recent versions of Dovecot (try 1.1.7).  Just posting that if anybody ever searches this.