Conserver problem

Hello all, I just joined this list,
I hope this is the appropriate address to use for troubleshooting questions,
and if not, please let me know.

I have been troubleshooting a conserver/console
issue for several months now, and I'm completely stuck. I have a Redhat
Linux (RHEL 4.4)
server that is hooked up to a Digi,
but when I try to console to that server, I get nothing. The logs show
that I have attached to the console,
but anything I type (carriage returns,
etc) are not echoed on the screen and do not show up in the console logs.
Our network team (responsible for
the physical cabling) has told me they
found no problem with it, and it used to work a few months ago. I've tried
restarting the console daemon
on the console server, rebooting/resetting
the digi, bouncing the dgrp processes, rebooting all the servers, and nothing
seems to work.

What indications should I look for to
see if this is a physical issue, or a software/config issue? How likely
is it that the port on the digi is bad?

Thanks in advance for your help, I'm
quite desperate at this point.

Thanks,
Tim