ICF and Port Forwarding

I have an Windows 2003 Server, Win 2000 Pro and Solaris 5.7 boxes. The Win 2003 Svr is connected to cable modem. It have two NICs. I have configured the ICF and ICS services and both machines can get to the outside world. However, I have a web server running ob both the Win2k and Sun boxes. I want to forward incomming requests accordingly. I have setup the ICF to forward request to port 8080 to the Win 2k box and port 8181 to the sun box. I have tested the web services locally between machines and it works. When I try to access the web server from the outside world, ie. http://ip:8080 and http://ip:8181. The Win2k or port 8080 work and the Sun box port 8181 does not. Both are setup to forward traffic from their repective ports to port 80. So, 8080 maps to 80 on Win2k and 8181 maps to 80 on SUN. I have tried the hosts names for each as well as their IPs but only the Windows box works. Any answers to this problem