[Freeswitch-users] How can I have the DIalplan choose the gateway for conference dialout?

Hi, I would like to use the Dialplan configuration to control which gateway is used on a conference dialout. I have a gateway configured in the Dialplan, to match any number. I have tried this on the dialout:    conference <name> dial {originate_timeout=30}sofia/external/8005551212 12345 CallerName but I get the errors    Cannot locate registered user 8005551212@external    mod_conference.c:6775 Cannot create outgoing channel, cause: USER_NOT_REGISTERED I don't want to specify the gateway in the dial request. I want the Dialplan to choose it. What am I doing wrong? Thanks, David