Hi all, This is a followup from my "Getting around semi-colons" question. I've specified: contact_user=01234567\;tgrp=01234567\;trunkcontext=telecom.co.nz under my registration section for the trunk. This is all fine and I successfully got Asterisk 13 + pjsip registered to our BroadWorks-based provider. However, I see the contact_user field only gets used upon registration, and not during an INVITE. During Registration: Contact: <sip: 01234567;tgrp=01234567;trunkcontext=telecom.co.nz at 192.168.252.10:5060> During INVITE: Contact: <sip:746775a8-e08c-4b73-a37e-fa48fe45a36b at 192.168.252.10:5060> The only questions I have is: 1. Is this expected/known behaviour? eg. pjsip won't use the contact user for anything else? 2. If not, where should I be specifying the contact_user to make pjsip use it in INVITEs? Is this where the AoRs come in? 3. Are those Contact headers used for some internal reference/record keeping for the calls? Or... 4. Can I mess with the Contact Header with the PJSIP_HEADER function? Thanks again for the help, just wrapping my head around this new channel driver :) Juan