Mapping Drives

We are trying to "Map" drives between a win98, win2000
and win XP systems over a peer-to-peer network to a Linux
(Redhat ver 7.2) and it gives a message that it cannot
find the network name, when trying to map to a specific
ip address of the Linux server. We have had this
function working for some time, then (not my call) it was
decided to move the Linux server offsite, and we have not
been able to reestablish the mapping since. Any
suggestions? Any experinece of this happening in a
similar situation. Needless to say, I'm getting the app.
people saying its the software and the software (both MS
and Linux) saying its the network - I think it probably
lies somewhere in between
thanks
David