Thank you all for your responses. Zoran has hit the bullseye, that describes our setup to a T. Are there any solutions to the problem, perhaps just working off the computer and not the network?
I submitted support request to Enfocus than it took long time to get any response.
Finally when I got response, they told me it is "known bug", probably known internally in Enfocus since their knowledgebase does not mention it.
Finally I was told it will be fixed in next update.
Next update 9.02 came and it wasn't fixed.
When I asked what happened to fix they said it was too close to release of 9.02 update so it will be in next, next update.
I've been waiting since than, probably couple of months now without hope.
In meantime I've had to uninstall Pistop 9 from all Mac production machines and revert them back to Pitstop 8 under Acrobat 9 which works ok. Pitstop 9 brought our Production to it's knees.
Be careful when you uninstall Pistop 9 not to leave any leftovers.
Here is good article on how to remove Pitstop 9 on Mac from Enfocus Knowledgebase:
http://www.enfocus.com/kb.php?id=6031
Good luck and keep an eye on next update of Pitstop, 9.03 if it ever comes out.