Index: includes/form.inc
===================================================================
RCS file: /cvs/drupal/drupal/includes/form.inc,v
retrieving revision 1.406
diff -u -9 -p -r1.406 form.inc
--- includes/form.inc	24 Nov 2009 21:56:15 -0000	1.406
+++ includes/form.inc	25 Nov 2009 19:04:44 -0000
@@ -1433,19 +1433,19 @@ function form_type_checkbox_value($eleme
       // Successful (checked) checkboxes are present with a value (possibly '0').
       // http://www.w3.org/TR/html401/interact/forms.html#successful-controls
       // For an unchecked checkbox, we return numeric 0, so we can explicitly
       // test for a value different than string '0'.
       return isset($input) ? $element['#return_value'] : 0;
     }
     else {
       // Disabled form controls are not submitted by the browser. Ignore any
       // submitted value and always return default.
-      return $element['#default_value'];
+      return $element['#return_value'];
     }
   }
 }
 
 /**
  * Helper function to determine the value for a checkboxes form element.
  *
  * @param $element
  *   The form element whose value is being populated.