diff --git a/kamailio/auth.cfg b/kamailio/auth.cfg
index 820264d..da10e32 100644
--- a/kamailio/auth.cfg
+++ b/kamailio/auth.cfg
@@ -64,7 +64,7 @@ route[SETUP_AUTH_HEADERS]
    #!ifdef REGISTRAR_ROLE
    $avp(is_registered) = "false";
    $xavp(regcfg=>match_received) = $su;
-   if (registered("location","$fu", 2, 1) == 1) {
+   if (registered("location","sip:$Au", 2, 1) == 1) {
         $avp(is_registered) = "true";
         $avp(auth_allowed) = "true";
         #!ifdef WITH_AUTH_TOKEN
@@ -73,6 +73,18 @@ route[SETUP_AUTH_HEADERS]
         route(AUTH_CCVS)
         #!endif
         return;
+   } else if(is_present_hf("Proxy-Authorization")) {
+        if(registered("location", "sip:$au@$ar", 2, 1) == 1) {
+            xlog("L_INFO", "$ci|auth|from sip:$au@$ar\n");
+            $avp(is_registered) = "true";
+            $avp(auth_allowed) = "true";
+            #!ifdef WITH_AUTH_TOKEN
+            route(AUTH_TOKEN);
+            #!else
+            route(AUTH_CCVS)
+            #!endif
+            return;
+        }
    }
    #!endif
 
diff --git a/kamailio/default.cfg b/kamailio/default.cfg
index 899efe5..0039932 100644
--- a/kamailio/default.cfg
+++ b/kamailio/default.cfg
@@ -632,8 +632,12 @@ route[SETUP]
 {
 
     if($sel(cfg_get.kazoo.strict_auth) == 1 && $avp(auth_allowed) != "true") {
-        xlog("L_WARN", "$ci|auth|request denied\n");
-        sl_reply("403", "Please Register");
+        if(is_present_hf("Proxy-Authorization")) {
+            xlog("L_WARN", "$ci|auth|request denied\n");
+        } else {
+            xlog("L_INFO", "$ci|auth|challenging invite\n");
+            proxy_challenge("$td", "4");
+        }
         exit;
     }