I need to be able to check the SIP response code to INVITE messages only. I don't care about BYE, CANCEL or anything else.
I tried putting a hint header in the INVITE when I sent it out, but the replies came back from the upstream provider with the header removed.
I tried setting a flag when an INVITE was received and using that. Didn't work.

How can I do this?
Is there a way to see what method a response is for? If there is, I could ignore everything that wasn't a response to an INVITE.

Thanks,
Doug.