Trixbox registration error 404

Hello!

I am an spanish user. Excuse me but my English level is so poor.

I have installed trixbox 2.0. I have created some extension like this (images 1 and 2). then I have configured X-lite softphone with this configuration (image 3, secret: 1000). The x-lite can’t register on the server (registration error - 404 not found). The server return error Sip 404 (I view it with wireshark sniffer)

(the images are posted in direct download on rapidshare, you don’t have to wait for)

http://rapidshare.com/files/60165052/1.JPG
http://rapidshare.com/files/60165075/2.JPG
http://rapidshare.com/files/60165104/3.JPG

Do you know what is the problem?

Thanks a lot!