Configure sip devices

Is it possible to configure sip device to go over IAX2?


I am using IAX2 to register to and its working ok.
Now I would like to make call using my sip devices. I know of people doing it but not sure how.
Do I have to enable and configure sip.conf? right now I have everything in sip.con commented out.

Than You.

Ok I got it configured and the other party hears me but I can not her them.

Any ideas?

I think I am almost there. I think I have to configure static out bound port mapping.