Problem with Outpost Pro, can someone help?

I've just setup Outpost pro on my win2k3 server and I'm having some difficulties getting it working so that my other pc's on the network can access the web.

I've done the detect thing for my network and its picked up the NTL and my lan connection, I've then trusted the lan connection so that it should allow all traffic to and from the lan connection. However when I go to the other PC's they just cant browse the web. They are able to ping some web sites. I think google & yahoo ping'd ok but msn just timed out.

The other PC's can also ping the NTL DNS servers and the default gateway.

I left the NTL connection set to not allow netbios and not be trusted (not sure about that?)

Have I done this wrong or have I just missed something?

Thanks :)