Ring incoming in 2 places at same time
 

Is it possible to register 2 sip devices in 2 different locations so I can ring out through either device on the same sip account and when an incoming call comes in both sip devices recieve the call at the same time? I've got 1 device working but I can't get the second device to register with the same credentials. These 2 devices are in different location and on different ip's.