Cisco IP phone register on second SIP server

Hi,

I have a cisco 7975 and i want two lines in different SIP servers(different IPs).
In the section i can use only “USECALLMANAGER” in xml node because register failed with IP address.

e.g


9
273
USECALLMANAGER
5060

How can i register the line 2 in a different sip (asterix)server?