Connected Line Updates
Digium phones support connected line updates using the P-Asserted Identity method. Connected line updates allow for dynamic caller id updates during call transfers. To enable Digium phones to receive and send updates, the SIP peer for the Digium phone must be setup using the trustrpid and sendrpid configuration options. Further, unless you are taking advantage of the Connected Line function, you will need to explicitly set a Caller ID for the PJSIP endpoint. Here is a basic example:
[myendpoint] aors=101 auth=101 callerid=Malcolm Davenport context = testing disallow = all allow = g722 trust_id_inbound = yes send_pai = yes