[Freeswitch-users] making calls through an FXO gw without knowing the IP

Hello everyone, I need some help in my dialplan, I have an FXO gateway and i can receive calls from it, now, if I assign a static IP on it, i can make calls through the fxo gateway using this: <action application="bridge" data="sofia/<profile>/<destination>@<gw_IP>"/> I want to know if it is possible to make calls through this gateway if it has a variable IP, and how to do it if so; the gateway uses SIP accounts to register to FS so i think it might be possible to route the call using one of the registered extension numbers but I am not sure how so I need some pointers, Anyone has ideas or knows how to do this?, help is greatly appreciated!