You can configure Presence Server to copy additional headers from incoming SUBSCRIBE requests to NOTIFY requests on the same session.
The 3GPP specification for SIP requires that an application server be able to extract certain types of headers from incoming SUBSCRIBE requests and insert them into the corresponding NOTIFY requests. For example, when an application server acting as an originating user agent (UA) issues a SUBSCRIBE request and receives a NOTIFY request, it expects to collect and use information from the P-Charging-Vector header that is included in the request.
You can configure Presence Server so that it includes copies specific types of headers from SUBSCRIBE requests and includes them in the NOTIFY requests it sends.
To arrange for one or more header types to be copied and included in NOTIFY requests, complete the following steps: