hdup not exiting on remote clients?

In the past 30 days or so, we've noticed 3 instances where remote hdup 
clients never exit and take up cpu time. However, backups complete 
successfully.

I haven't been able to nail down any exact circumstances around what 
might be causing this. It seems to always happen to clients running in 
remote data centers, though that may be because we have only 3 machines 
(out of ~25) local to the hdup server. We are running hdup-2.0.5 everywhere.

Has anyone seen this issue? Any ideas on what might be causing this? 
Thanks for any help you can provide.