Hello there. I'm working in a scenario in which FreeSWITCH acts as a media server and all SIP signaling is proxied through Kamailio. Every call that comes in to FreeSWITCH is simply bridged back to Kamailio and on to destination network. Registration bypasses FreeSWITCH, so 401 REGISTER challenges are dealt with by the UE directly. Now I need to talk to a network which demands INVITEs are authenticated as well. when the target network responds with a 407 Proxy Authentication Required, FreeSWITCH terminates the dialog and fs_cli shows the following error: [ERR] sofia_reg.c:2583 Cannot locate any authentication credentials to complete an authentication request for realm '"<whatever>"' Is there any way I can instruct FreeSWITCH to relay the 407 challenge back to the UE, so the authenticated INVITE can also be blindly bridged by FreeSWITCH? Thanks.