I had the problem that due to an incorrectly configured ssh the pbs_mom couldn't send the finished data (.ER and .OU files) back to the server. After a look into the log, I could locate the data on the nodes in the /var/spool/torque/undelivered/ directory.
Now I have correctly configured the ssh connection. Is there a way to automatically gather the data in undelivered (resp. signal the pbs to retry) or do I have to do this manually?