One change, the call to seturi is actually:
seturi("sip:feature_fs@_sip._udp.aimcidfilter.com:6010");
>
_sip._udp.aimcidfilter.com 180 IN SRV 1 50 5061
crunch.com.
>
_sip._udp.aimcidfilter.com 180 IN SRV 1 50 5061
spinner.com.
>
_sip._udp.aimcidfilter.com 180 IN SRV 2 50 5061
homer.com.
>
_sip._udp.aimcidfilter.com 180 IN SRV 2 50 5061
bart.com.