diff --git a/date_api/date_api_elements.inc b/date_api/date_api_elements.inc
index 7da4e58..cc6f016 100644
--- a/date_api/date_api_elements.inc
+++ b/date_api/date_api_elements.inc
@@ -529,7 +529,7 @@ function date_parts_element($element, $date, $format) {
     $part_type = in_array($field, $element['#date_text_parts']) ? 'textfield' : 'select';
     $sub_element[$field] = array(
       '#weight' => $order[$field],
-      '#required' => $part_required,
+      '#required' => (bool) $element['#required'],
       '#attributes' => array('class' => isset($element['#attributes']['class']) ? $element['#attributes']['class'] += array('date-' . $field) : array('date-' . $field)),
       '#ajax' => !empty($element['#ajax']) ? $element['#ajax'] : FALSE,
     );