[dba-SQLServer]SQL server on VLAN, in own workgroup

Hello all,

I have a situation.. 

Setup is Win2K desktop, Win2k SErvers (mix mode Active Directory), SQL
SErver 2000.

The company I work for has a main office in Pittsburgh, and 2 manufacturing
plants (one in Port Allegany, PA, and one Sedalia, Missouri).  We are
connected VIA a WAN.  In our Port Plant, we are implementing new technology
to gather defect information from the plant floor.  This information will be
held in a sql server database.  The software company recommends this system
be separated by a VLAN which has been set up and is working.  They also
recommend having this sql server, PLC, and 2 other machines be exclusively
on their own network of which a workgroup was set up.  I'm not a network
kind of guy, know enough to get around but that's about it.  

So now I'm the SQL server person here.  I'm new to it, learning it as I go
with a 5 day class under my belt.  We have quite a few sql server database
servers doing various things, all of which I have taken responsibility for.
I connect to all of them using Enterprise Manager on my machine.  I cannot
connect to the new SQL server that is on the VLAN.  I can ping the server,
however using the IP address I cannot register the server with my Enterprise
Manager.  

Has anyone done this, or know how to do this?

Rich