diff --git a/cake/libs/view/helpers/form.php b/cake/libs/view/helpers/form.php
index a6bbe2540..581746bdb 100644
--- a/cake/libs/view/helpers/form.php
+++ b/cake/libs/view/helpers/form.php
@@ -169,7 +169,8 @@ class FormHelper extends AppHelper {
  *
  * - `type` Form method defaults to POST
  * - `action`  The controller action the form submits to, (optional).
- * - `url`  The url the form submits to. Can be a string or a url array,
+ * - `url`  The url the form submits to. Can be a string or a url array.  If you use 'url'
+ *    you should leave 'action' undefined.
  * - `default`  Allows for the creation of Ajax forms.
  * - `onsubmit` Used in conjunction with 'default' to create ajax forms.
  * - `inputDefaults` set the default $options for FormHelper::input(). Any options that would