I got calls to go to an IPV6 phone by copying this line from default.xml: <param name="dial-string" value="{sip_invite_domain=${dialed_domain},presence_id=${dialed_user}@${dialed_domain}}${sofia_contact(${dialed_user}@${dialed_domain})}"/> to the user extension.xml and changed it to: (this works fine) <param name="dial-string" value="{sip_invite_domain=${dialed_domain},presence_id=${dialed_user}@${dialed_domain}}${sofia_contact(internal-ipv6/ ${dialed_user}@${dialed_domain})}”/> my question is do I need to add internal-ipv6 also to presence_id like this: <param name="dial-string" value="{sip_invite_domain=${dialed_domain},presence_id=internal-ipv6/${dialed_user}@${dialed_domain}}${sofia_contact(internal-ipv6/ ${dialed_user}@${dialed_domain})}”/> Mario G