[Dovecot] more dsync problems: Error: proxy client timed out

Hi all, I'm using dsync for backups. I recently upgraded to 2.1.7 due to issues with dsync mirror/backups. 2.1.7 fixed the issue with the guid conflict, but now I'm seeing this error on a couple of mailboxes:

Error: proxy client timed out (waiting for output stream to flush, 0 bytes left)

If there are 0 bytes left, why is it trying to flush? I'm using this

command to backup the mailbox:

dsync -vo mail_home=/home/users/user%domain.com backup ssh vmail@10.1.2.2 dsync -o mail_home=/home/.incoming_mail_migrations/users/user%adomain.com

Any ideas? 

		...Jeff