default route tweaks

* clean proxy-authorization
* fix log line
* don't forward ack without destination set

(cherry picked from commit 726784b)

Author: lazedo

kamailio/default.cfg

@@ -260,6 +260,7 @@ route[MAIN]
     if (!isflagset(FLAG_INTERNALLY_SOURCED)) {
         route(AUTHORIZATION);
         remove_hf("Authorization");
+        remove_hf("Proxy-Authorization");
     }
 
     #!ifdef MESSAGE_ROLE
@@ -321,7 +322,7 @@ route[LOG_REQUEST_CLASSIFIED_SOURCE]
     } else if (isflagset(FLAG_TRUSTED_SOURCE)) {
         xlog("$var(log_request_level)", "request from trusted IP\n");
     } else if (!isflagset(FLAG_NETWORK_CLASSIFIED)) {
-        if (is_myself("$ou")) {
+        if (is_myself("$ou") && !has_totag()) {
             xlog("$var(log_request_level)", "original R-URI ($ou) is this proxy, treating as external sources\n");
         } else {
             xlog("$var(log_request_level)", "originated from external sources\n");
@@ -727,6 +728,11 @@ route[EXTERNAL_TO_INTERNAL_RELAY]
 
 route[RELAY_TO_INTERNAL]
 {
+    if (is_method("ACK") && has_totag() && !isdsturiset()) {
+        xlog("L_INFO", "ACK - end\n");
+        return;
+    }
+
     if (is_method("INVITE|BYE|SUBSCRIBE|UPDATE|NOTIFY|CANCEL|REFER")) {
         if(!t_is_set("branch_route")) t_on_branch("MANAGE_BRANCH");
     }