diff --git a/wp-admin/edit-form.php b/wp-admin/edit-form.php
index 3837fa3f31..fd5efcea9b 100644
--- a/wp-admin/edit-form.php
+++ b/wp-admin/edit-form.php
@@ -64,7 +64,7 @@ edCanvas = document.getElementById('content');
 <?php if ('bookmarklet' != $mode) {
       echo '<input name="advanced" type="submit" id="advancededit" tabindex="7" value="' .  __('Advanced Editing &raquo;') . '" />';
   } ?>
-  <input name="referredby" type="hidden" id="referredby" value="<?php if (isset(wp_get_referer())) echo urlencode($_SERVER['HTTP_REFERER']); ?>" />
+  <input name="referredby" type="hidden" id="referredby" value="<?php if ( wp_get_referer() ) echo urlencode(wp_get_referer()); ?>" />
 </p>
 
 <?php do_action('simple_edit_form', ''); ?>