Internet Connection Sharing with XP machine

I have a client that has an existing XP desktop which is using a Verizon Wireless broadband device for an internet connetion (no other broadband available in the area). So he simply connects to it wirelessly and he gets his internet.

Complication starts here. He just got a Windows 7 laptop and needs to share the internet connection of the Verizon device. Only problem is that the laptop is out of range of the verizon device. So, we have a Linksys wireless router that is connected to the XP machine and gives us the range we need to reach the laptop.

My trouble is that I can't get any sort of connection between the two computers. They are on the same workgroup and I have enabled everything in the sharing options on the Win7 machine. My goal is to have the Win7 laptop connect to the XP machine and share the internet connection and printer and files etc...

Here is a diagram of the situation. I've had one person tell me he doesn't think it's possible. But I bet there is a way.



Any help would be appreciated!

The VZW device is strictly wireless only. The only plug is for a power cord to charge it. All it is, really, is a modified 3g cell phone that wireless devices connect to get internet. I'll work on getting you the IP configs. My client won't be back around till monday.

Right now the IPs might be setup in a fashion that would allow ICS because I thought that might be necessary. But the network configuration file created by the XP machine didn't appear to work on the 7 machine.