=== modified file 'includes/form.inc'
--- includes/form.inc	
+++ includes/form.inc	
@@ -62,7 +62,7 @@ function drupal_get_form($form_id, &$for
       variable_set('drupal_private_key', mt_rand());
     }
 
-    $form['form_token'] = array('#type' => 'hidden', '#value' => md5($_SERVER['REMOTE_ADDR'] . $form['#token'] . variable_get('drupal_private_key', '')));
+    $form['form_token'] = array('#type' => 'hidden', '#value' => md5(session_id() . $form['#token'] . variable_get('drupal_private_key', '')));
   }
   $form['form_id'] = array('#type' => 'hidden', '#default_value' => $form_id);