Norton Firewall 2004

Ok i have a 2 computers on a LAN both sharing the same ADSL internet connection. The host computer has the ADSL modem and my computer connects to it for the internt connection. However ever since Norton Personal Firewall 2004 has been installed on the host computer the internet will not work on my computer. It will only work when the firewall is disabled. I have tried allowing the IP adresses but they keep changing is there anway i can get around this. All i want is to use both computers on the internet with a firewall enabled.

If anyone can help it would be really appreciated.

Garnz