It is not complex to establish a tcp connection between a XP and the Z via USB. The zaurus and XP is almost automatic.
On the zaurus check the USB setup with the the command ifconfig. You should have a en entry named usbd0 . Probably with an IP address 192.168.129.201 .
If this is missing then set it up with th USB function tool in the system folder (fill in Network, IP and netmask (255.255.255.0) and click OK.
Then do the following command where xxx ist th IP on the XP you are connected to :
route add -host xxx usbd0
Then the zaurus is ready !
On the XP if you have installed the usb drivers you can configure your IP or let it be set automatic . I have configured it to 192.168.1.100 . (to configer right click your net icon for the usb LAN and under General open properties under TCPIP )
Then you need to open a dos window and do the following command where zzz is the IP on your Zaurus and xxx is the IP on your XP:
route add zzz xxx
If you want to telnet to your Zaurus you need to setup and install a telnet demon, but this is not recomended. Rather use ssh because the pdaxrom comes with a ssh server pr default. From the XP use the ssh client putty (search for putty.exe at google) .
I use Cygwin on my XP with ssh and X server which I consider to be the best way to do ssh and X forwarding.