diff --git a/kamailio/default.cfg b/kamailio/default.cfg
index 49573b6..95e6b8b 100644
--- a/kamailio/default.cfg
+++ b/kamailio/default.cfg
@@ -447,7 +447,7 @@ route[INTERNAL_TO_EXTERNAL_RELAY]
     }
     #!endif
 
-    remove_hf_re("X-.*");
+    remove_hf_re("^X-.*");
 
     t_on_reply("EXTERNAL_REPLY");