Intel Mac Disconnect from the Server After Print Jobs

One of our schools has about 30 eMacs (about 2 years old) and two new
iMacs running on a cross platform network. I haven’t had any trouble
with the eMacs but the two new iMacs are having trouble printing.

They both print fine when logged in under the local account but once a
networked account is logged in the computer will disconnect from the
server and has to be logged off and back in to reconnect. Both iMacs
are running OS X 10.4.10 and have all recent updates.

Please help!!