XP Internet Connection Sharing

Hi Everyone,

I'm new on Mac OS X, and now I'm using Leopard in my macbook.
I have a problem to connect to the internet via Windows XP Internet Connection Sharing.
Here is the scenario:

Internet
|
|
MS ISA Server
|
|wireless
|
Windows PC------------------ Macbook
UTP Cable

There are 1 wireless connection which connect to internet through Microsoft ISA Server and1 LAN Card that I use to connect to my Macbook via UTP cable.
I can see the IP address of the PC's LAN Card from my Macbook, but how can I see the IP of the wireless card?
How to connect to Win XP Internet connection sharing from Leopard?


Thank you....