looks like kamailio dont unerstand that he need handle 407 request At my side i see that kamailio dont stops 407 request and resend it without any handling I use asterisk->kamailio-provider scheme
At this scheme kamailio must stops proxy of get 407/401 and then make another invite with www-auth header
But it proxies 407 to asterisk back. and give errors above.
if (t_check_status("401|407")){ xlog("L_INFO", "Reply from provider on failure: $tU"); xlog("L_ERR","401/407 - Unauthorized. ($ci .) ($rm) from ($fu) (IP:$si:$sp) to ($Ri:$Rp). Must be authorized with digest Auth.");
if (uac_auth()) { xlog("L_INFO", "CSeq diff: $dlg_var(cseq_diff)"); t_relay(); } else { xlog("L_INFO", "UAC_AUTH(): credentials not found"); } t_relay(); }