Norton Ghostcast Issue

I am currently ghosting a lab of dell’s and having some issues. I set up the ghostcast server and get most of the clients to connect automatically in multicast, some i have to type in the server ip, which is odd, no clue why. Once all are setup and i start the session, after 10 minutes the projected time will pop up, and it is something insane like 212 days… all the machines say loading ntfs mft …. after 30 some odd minutes half of the machines will fail and the session doesn’t seem to have gone anywhere. i do not have this issue when i tried mutlicasting to just one or two machines. any ideas?