diff --git a/captcha_img.php b/captcha_img.php
--- a/captcha_img.php
+++ b/captcha_img.php
@@ -1,4 +1,4 @@
-<?php
+<?php /* -*- mode: php; -*- */
 /*
  * Copyright 2010 Nathan Gelderloos, Ethan Zonca, Nathan Phillip Brink
  *