--- a/libpurple/plugins/caesarcipher.c	Mon Nov 18 00:03:23 2013 +0530
+++ b/libpurple/plugins/caesarcipher.c	Mon Nov 18 01:12:39 2013 +0530
@@ -23,7 +23,12 @@
  * 02111-1301, USA.
  */
 
-#include <internal.h>
+/* When writing a third-party plugin, do not include libpurple's internal.h
+ * included below. This file is for internal libpurple use only. We're including
+ * it here for our own convenience. */
+#include "internal.h"
+
+/* This file defines PURPLE_PLUGINS and includes all the libpurple headers */
 #include <purple.h>
 
 #include "caesarcipher.h"