diff --git includes/ajax.inc includes/ajax.inc
index f77bd90..fe25109 100644
--- includes/ajax.inc
+++ includes/ajax.inc
@@ -26,22 +26,24 @@
  *
  * @see @link ajax_commands AJAX framework commands @endlink
  *
- * To implement AJAX handling in a normal form, just add '#ajax' to the form
+ * To implement AJAX handling in a normal form, add '#ajax' to the form
  * definition of a field. That field will trigger an AJAX event when it is
  * clicked (or changed, depending on the kind of field). #ajax supports
  * the following parameters (either 'path' or 'callback' is required at least):
+ * - #ajax['callback']: The name of a function which will be called when the AJAX
+ *   functionality is invoked. Receives $form and $form_state as arguments, and
+ *   returns the HTML which will replace the element named in #ajax['wrapper'].
+ *   This is an easier technique to use than #ajax['path'], but may not meet every
+ *   need as #ajax['path'] is more powerful. Note that #ajax['callback'] currently only
+ *   works for buttons (submit, button, image button) and not for other element types.
  * - #ajax['path']: The menu path to use for the request. This path should map
  *   to a menu page callback that returns data using ajax_render(). By default,
- *   this is 'system/ajax'. Be warned that the default path currently only works
- *   for buttons. It will not work for selects, textfields, or textareas.
- * - #ajax['callback']: The callback to invoke, which will receive a $form and
- *   $form_state as arguments, and should return the HTML to replace. By
- *   default, the page callback defined for the menu path 'system/ajax' is
- *   triggered to handle the server side of the #ajax event.
- * - #ajax['wrapper']: The CSS ID of the AJAX area. The HTML returned from the
- *   callback will replace whatever is currently in this wrapper. It is
- *   important to ensure that this wrapper exists in the form. The wrapper is
- *   usually created using #prefix and #suffix properties in the form.
+ *   this is 'system/ajax'. If you use a custom path, you must set up the menu entry
+ *   and handle the entire callback in your own code.
+ * - #ajax['wrapper']: The CSS ID of the area to be replaced by the HTML returned by
+ *   the #ajax['path'] function. The HTML returned from the
+ *   callback will replace the entire element named by #ajax['wrapper'].
+ *   The wrapper is usually created using #prefix and #suffix properties in the form.
  * - #ajax['effect']: The jQuery effect to use when placing the new HTML.
  *   Defaults to no effect. Valid options are 'none', 'slide', or 'fade'.
  * - #ajax['speed']: The effect speed to use. Defaults to 'slow'. May be
@@ -54,6 +56,10 @@
  *   Defaults to 'replace'. May be: 'replace', 'append', 'prepend',
  *   'before', 'after', or 'html'. See the jQuery documentation for more
  *   information on these methods.
+ * - #ajax['progress']: Choose either a throbber or progress bar that is displayed
+ *   while awaiting a response from the callback, and add an optional message.
+ *   Possible keys: 'type', 'message', 'url', 'interval'. More information is available
+ *   in the Form API Reference.
  *
  * In addition to using Form API for doing in-form modification, AJAX may be
  * enabled by adding classes to buttons and links. By adding the 'use-ajax'