Index: modules/image/image.field.inc
===================================================================
RCS file: /cvs/drupal/drupal/modules/image/image.field.inc,v
retrieving revision 1.16
diff -u -p -r1.16 image.field.inc
--- modules/image/image.field.inc	17 Feb 2010 05:39:51 -0000	1.16
+++ modules/image/image.field.inc	20 Feb 2010 15:06:49 -0000
@@ -313,6 +313,10 @@ function image_field_widget_settings_for
  * Implements hook_field_widget_form().
  */
 function image_field_widget_form(&$form, &$form_state, $field, $instance, $langcode, $items, $delta, $element) {
+
+  // Add display_field setting to field because file_field_widget_form() assumes it is set.
+  $field['settings']['display_field'] = 0;
+
   $elements = file_field_widget_form($form, $form_state, $field, $instance, $langcode, $items, $delta, $element);
   $settings = $instance['settings'];