Remote Extension issues

Ok so I’ve got an issue with my freepbx distro. Ive got my machine behind a firewall and nat’d. Ive got an extension set up and softphone on my iPhone. When my iPhone try’s to connect to the server zoiper will register just fine. But when I take one of my aastra 6757i’s out in the field it will not resolve the connection. When I looked at the debug log its telling me the extension cannot register due to an incorrect password but i don’t see that being the issue?

Any help or maybe a checklist of different things that should be turned on would be great!


Also i was wondering maybe the firewall of my pbx is the issue? Does IPTables and F2B allow sip traffic through by default?

Anyone have any ideas on this for me?! i’ve turned off all the firewalls and made sure my nat settings are all set to yes and even forwarded port 80 temporarily just to test and my phone would still not prompt me for an extension login!!! i’m lost on this