Failing miserably to network 2 PCs

I have PC number 1 running W98SE (which connects very happily to the
internet via a Realtek RTL8139 NIC). It has a second onboard Realtek
RTL8169. I am attempting to use this to connect to a second PC (running XP
but never been near the internet) via a CAT5 crossover cable to the second
PCs Realtek RTL 8139 NIC.

I have tried using the XP Network wizard to connect the two PCs. It runs
and tells me it is done and everything is set up but neither PC sees the
other. The only indication I do get is that the XP PC will pop up a message
saying the LAN cable is unplugged if I turn off or re-boot the W98 PC.

I have tried to set up an IP address on the XP machine and ping it from the
W98 PC but this invariably times out.

Both PCs show no problems with any of the network cards under the Device
Manager.

What have I missed? Or should I give up and go back to slow but (fairly)
reliable Direct Cable Connection?

Zippy