Pinging RAS Server

I have a WINNT ras server on my network and have remote Win98 clients dialing in. The MS Exchange server is also on the RAS server. The problem is that I can ping the ras server using the IP address, but not using it’s netbios name. I can ping all other servers using ther netbios name when dialed in except the server I am dialed into. This causes the remote mail users problem in resolving the MS exchange server name. I have used both LMhosts and hosts files but to no avail unless I am using an incorrect format for these files.

Need help Seriously…