I have a 400 processor on 4.2 software and I am working with SIP Trunking. The IT guy at this site wants to put a firewall inbetween the IPO and the ITSP. Because of this the PBX will now have an internal IP and the firewall will now take the external IP and forward packets to the IPO. The IP office is 192.168.1.240 and the sonicwall firewall is 192.168.1.18. What do I need to change in Manager besides the LAN 1 tab obviously, I put in an IP route that lists the firewall as the gateway as well.