MS VPN 2000 Routing

I have setup a New MS Win2000 VPN server. We have 4 different subnets and I have created static routes for all the subnets. The VPN server is giving out DHCP addresses from our pool, but when we connect to the vpn server we cannot get back out to the internet. We have a PIX Firewall and it is reading this as the IP address of the VPN servers Public address instead of using the new ip address given when you connect to the vpn server. Any ideas???