Core Issue
When a call comes into Cisco CallManager from the Public Switched Telephone Network (PSTN), the calling number does not include the required prefix for outside dialing. If the user navigates to the missed call and selects dial, the call fails since no outside line is seized.
In North America, the required prefix is 9 and in Australia it is 0.
Resolution
Configure a translation rule on the gateway to prepend the 9 in the calling party number. This prefix is applied to calling party numbers from the PSTN as they are forwarded out the Voice over IP (VoIP) dial peer towards Cisco CallManager.
translation-rule 1
Rule 1 ^.% 9
Dial-peer voice 1 voip
Translate outgoing calling 1
!--- Apply translation-rule 1 to the calling number
!--- of any call outbound on the VoIP dial peer.
!--- That is, change the calling number
!--- of any call from the PSTN by adding a 9 in
!--- front of it.
Destination-pattern 4...
session target ipv4:10.1.1.1
