Win98/WinXP home network

Hello

I hope someone can help me. I am putting together a small home network
using a router and Ethernet adapters.

It hasn't started too well. Right now I have only two computer on the
network, one using Win98 and the
other WinXp SP2. Both access the internet OK through the router and the XP
computer can see the 98 one in "Network Places", but the 98 one cannot see
the XP one either in the network places or using UNC (startrun\\computer
name). Both are in the same (and only) work group. I have checked that the
NICs are working properly, have tied adjusting a number of software
settings,
taking Windows Firewall off the XP system, etc but to no avial. Am I
missing something basic? What else should I try?

Any ideas would be much appreciated

Mike