Cannot register freepbx extensions with softphone

I installed freepbx and had this error:
Cannot connect to Asterisk Manager with admin
Asterisk may not be running.

I solved it changing enabled to yes and adding the admin user in manager.conf.
Now i can access freepbx with firefox and create sip extensions whit no problems. but when i try to log with the extension in the soft phone (i use ekiga) it can’t register.

I know asterisk works because i create two extension editing the file extensions.conf and sip.conf and they works fine with ekiga. This extensions don’t appears in freepbx.

What i’m doing wrong?

My system is:
Ubuntu 7.04
asterisk 1.2.16
freepbx 2.2.2
zaptel 1.2.18
libpri 1.2
php 5.2.1
apache 2.2.3