Hello,everyone.
Ive tried to use a1-hash instead of username and password.(when i use plain username and password everything works fine).
However, freeswitch does not allow users to register,when i use domain which is different from ip_address of the Freeswitch server.
I am using domain - nick.sfedu.
Domain in vars.xml,directory/default.conf is set as nick.sfedu and force-register-domain in internal profile is set to the same value.
When I use plain username and password, i can see the following:

Call-ID:        NGJhMDU5NTM0MDllZWY2ODllZjFjYzMwYzAzMzQxMTc
User:           11007@nick.sfedu
Contact:        "Nick" <sip:11007@10.132.144.157:49610;rinstance=fd2236fab37d0ba1;fs_nat=yes;fs_path=sip%3A11007%4010.132.144.157%3A49610%3Brinstance%3Dfd2236fab37d0ba1>
Agent:          X-Lite 4.7.1 74247-a844961e-W6.1
Status:         Registered(UDP-NAT)(unknown) EXP(2015-07-24 14:55:08) EXPSECS(144)
Host:           fsw1-test
IP:             10.132.144.157
Port:           49610
Auth-User:      11007
Auth-Realm:     10.160.1.23
MWI-Account:    11007@nick.sfedu

where 10.160.1.23 is ip address of the Freeswitch server,but it should be nick.sfedu,as far as i understand.
Best regards,
Nikolay Zaytsev