[Serusers] help with the setup of Ser.

Hello people... I have been working on Ser all day. I have read every manual possible, and am about to lose it! My setup is pretty simple. Ser is running on 192.168.3.1... it is a dhcp server, tftp server, and ser server. I have 2 Cisco IP Phones (7960)... They both connect to 192.168.3.1 just fine. They download the latest rom, they have the appropriate lines in the top right of the screen. Everything seems fine, until I attempt to make a call. Running serctl monitor shows me that everytime a call is placed, it gets an error 404 - Not Found. I was getting error 483 earlier, but I read the documentation some more and fixed it. I have setup locations for the two users (sip:chris@192.168.3.1) and (sip:allan@192.168.3.1), and aliases as well.. Still, I cannot make a call between the two phones. Everytime I try, I get a busy tone on the phone, and error 404... Can anyone please help? Thanks!