Index: modules/field_ui/field_ui.admin.inc
===================================================================
RCS file: /cvs/drupal/drupal/modules/field_ui/field_ui.admin.inc,v
retrieving revision 1.69
diff -u -p -r1.69 field_ui.admin.inc
--- modules/field_ui/field_ui.admin.inc	26 Sep 2010 23:31:35 -0000	1.69
+++ modules/field_ui/field_ui.admin.inc	29 Sep 2010 02:16:18 -0000
@@ -1448,7 +1448,7 @@ function field_ui_field_settings_form($f
   // If so, prevent changes to the field settings.
   $has_data = field_has_data($field);
   if ($has_data) {
-    $form['field']['#description'] = '<div class=error>' . t('There is data for this field in the database. The field settings can no longer be changed.' . '</div>') . $form['field']['#description'];
+    drupal_set_message(t('There is data for this field in the database. The field settings can no longer be changed.'), 'error');
   }
 
   // Build the non-configurable field values.