Index: includes/form.inc
===================================================================
RCS file: /cvs/drupal/drupal/includes/form.inc,v
retrieving revision 1.441
diff -u -r1.441 form.inc
--- includes/form.inc	12 Mar 2010 14:38:37 -0000	1.441
+++ includes/form.inc	13 Mar 2010 17:27:15 -0000
@@ -1756,11 +1756,13 @@
 }
 
 /**
- * Change submitted form values during form validation.
+ * Changes 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 the remaining validation and 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