diff --git a/Makefile.include b/Makefile.include
index ceccb9c7b..e8251c921 100644
--- a/Makefile.include
+++ b/Makefile.include
@@ -1,3 +1,5 @@
+# -*- makefile -*-
+
 ifndef CONTIKI
   ${error CONTIKI not defined! You must specify where CONTIKI resides}
 endif