- specifying an invalid module will redirect you to the index page instead of

  showing a blank page.

module.php

@@ -3,10 +3,13 @@
 
 include_once "includes/common.inc";
 
-page_header();
-
-module_invoke($mod, "page");
-
-page_footer();
+if (module_hook($mod, "page")) {
+  page_header();
+  module_invoke($mod, "page");
+  page_footer();
+}
+else {
+  header("Location: index.php");
+}
 
 ?>