Probably your users might not be in the default context. To make call from one sip user to another both must be in same context. For testing purpose you may want to keep both of them in default context. In the user_name.xmlfile put context = default , this may solve your problem.
My both extensions are in default context .To crosscheck it i used list_users command at fs_cli console and it shown
that both phones are in default context.Here is output of list_users
1100|default|192.168.8.41|default|sofia/internal/sip:1100@192.168.9.165:29072;rinstance=ee8af9a648b2e70d||Vivekanandm|1100
1101|default|192.168.8.41|default|sofia/internal/sip:1101@192.168.8.103:26196;rinstance=a6ab3905d800b8f7||navnath|1101
As you suggested put context = default in user_name.xml
but i did not find user_name.xml file in my freeswitch directory.
Can you please tell me where to locate this file?
Regards,
Navnath.