kamailio.cfg: do sanity check by default

- use sanity module to catch parsing errors early in config
- replaces error_route from kamailio 1.5

etc/kamailio.cfg

@@ -126,6 +126,7 @@ loadmodule "textops.so"
 loadmodule "uri_db.so"
 loadmodule "siputils.so"
 loadmodule "xlog.so"
+loadmodule "sanity.so"
 loadmodule "acc.so"
 /* uncomment next lines for MySQL based authentication support 
    NOTE: a DB (like db_mysql) module must be also loaded */
@@ -265,6 +266,12 @@ route{
 		exit;
 	}
 
+	if(!sanity_check("1511", "7"))
+	{
+		xlog("Malformed SIP message from $si:$sp\n");
+		exit;
+	}
+
 	# NAT detection
 	route(NAT);