Index: includes/form.inc
===================================================================
RCS file: /cvs/drupal/drupal/includes/form.inc,v
retrieving revision 1.430
diff -u -r1.430 form.inc
--- includes/form.inc	4 Feb 2010 03:34:20 -0000	1.430
+++ includes/form.inc	5 Feb 2010 15:28:23 -0000
@@ -1738,11 +1738,13 @@
 }
 
 /**
- * Change submitted form values during form validation.
+ * Change submitted form values (in $form_state) during form validation.
  *
  * Use this function to change the submitted value of a form element in a form
  * validation function, so that the changed value persists in $form_state
- * through to the submission handlers.
+ * through to the submission handlers. It does not change the values that may
+ * be present in the $element array, but only in $form_state, which is where
+ * the submitted values are always stored.
  *
  * Note that form validation functions are specified in the '#validate'
  * component of the form array (the value of $form['#validate'] is an array of