I am trying to implement some basic functionalities of http://tools.ietf.org/html/draft-ietf-soc-overload-control-00 (SIP Overload Control) and now I need to add some parameters to the own Via-header. I want to add the string ";oc" to the Via-header added to the SIP request.
Using the "subst"-command like "subst('/^Via: .*/Via: $(hdr(Via));oc^C\n/')" does only affect the Via-header in the received request, but I can't find a way to add this string to the Via-header which is added by the proxy before the request is forwarded to the next hop.
Any ideas are welcome!
Thx in advance