Allow internal Machines to acces an http server on the Firewall

Hi guys... I had a SuSE 8.0 box acting as a Firewall (with 2 nics)... it also had installed an Apache Web Server, and my problem is that any of my internal Pc's can't reach any service at the Firewall Box. I setup the Firewall Rules using YaST, and even set to don't protect the Firewall from the internal Network... Any clue of how to setup or modify that box in order to allow internal traffic to legitime services provided by the Firewall on my internal Network ? Thanks !! bye --ed