I just setup a new system with Ubuntu 12.04 and shorewall and I'm having an issue where web traffic is not working from the local net to the Internet, however pings from the local net to google work.  All files right now are the defaults from the 2 interface example though I have set the IP_FORWARDING setting to on and have even set a rule of ACCEPT loc net all without a change in behavior.
Please shed some light on this problem because I am baffled.