[Users] Problem with proxydispatcher

Hi all, I have problem with dispatcher following: When i see in proxydispatcher have support "Distributed geographical location" I call setup call: caller (from: 101(a)hanoi.openser.com) ----> callee(200(a)danang.openser.com). In openser.cfg i use "use_media_proxy();" and "modparam("mediaproxy","mediaproxy_socket","/var/run/proxydispatcher.sock")" I set defaultProxy = None in mediaproxy.ini file to dispatcher selected mediaproxy based on the SIP domain of the caller/destination using DNS SRV records. On DNS i have mediaproxy for domain hanoi.openser.com is media1.hanoi.openser.com, for domain danang.openser.com is media1.danang.openser.com But dispatcher no select domain based on the SIP domain of the caller/destination. Please help me. Thanks.