print jobs get cancelled

I have a network with a shared printer. If one person is printing and
another submits a job the first person's job gets cancelled and the second
job takes over.

This is a network printer installed on a server and shared from there (it's
a Windows 2000 server). All other printers seem to be working fine. Only
this one printer (and HP 4200) is having this issue. I don't see anything in
the log files why this is happening. What can I look at to troubleshoot this
problem?

Bill