Im taking a guess here, but I think you are probably trying to build a VPN between the Ravlin client software and a PIX. If that is what you are trying to do I dont think it can be done. Their client is designed to build a VPN between itself and their concentrator product. You can set the concentrator behind the PIX and open up esp and udp to make it work, but Id just go with the Cisco VPN client to the PIX. I havent actually tried terminating at the PIX with Ravlinsoft, but maybe someone here has.