diff --git a/sites/all/modules/contrib/hierarchical_select/hierarchical_select.module b/sites/all/modules/contrib/hierarchical_select/hierarchical_select.module
index c525adf..84f8bd6 100644
--- a/sites/all/modules/contrib/hierarchical_select/hierarchical_select.module
+++ b/sites/all/modules/contrib/hierarchical_select/hierarchical_select.module
@@ -556,6 +556,52 @@ function _hs_process_exclusive_lineages($element, $hs_selection, $db_selection)
 
 function _hs_process_render_create_new_item($element, $hierarchy) {
   $creating_new_item = FALSE;
+
+  /* This container and the "Create" / "Cancel" buttons must always be part of
+   * the form, even when HS is not in create mode, in order for AJAX submit
+   * callbacks on the "Create" and "Cancel" buttons to be processed correctly.
+   *
+   * Basically, FAPI looks through each of the buttons in the form to determine
+   * which one was clicked. If it can't find the responsible button, it
+   * assumes it was the first button in the form. This is problematic when the
+   * user clicks on the "Create" or "Cancel" buttons because we only want them
+   * to show up when HS is in create mode. To fix this, we always render the
+   * buttons as part of the form, then disable access to them in an
+   * "#after_build" callback.
+   *
+   * This might not be necessary if we used D7's native AJAX callback function,
+   * ajax_form_callback().
+   */
+  $element['hierarchical_select']['create_new_item'] = array(
+    '#prefix' => '<div class="create-new-item">',
+    '#suffix' => '</div>',
+    '#after_build' => array('hierarchical_select_create_new_item_after_build'),
+  );
+
+  // TODO: Port to use built-in D7 AJAX callback?
+  $element['hierarchical_select']['create_new_item']['create'] = array(
+    '#type' => 'submit',
+    '#value' => t('Create'),
+    '#attributes' => array('class' => array('create-new-item-create')),
+    '#limit_validation_errors' => array($element['#parents']),
+    '#validate' => array(),
+    '#submit' => array('hierarchical_select_ajax_update_submit'),
+  );
+
+  $element['hierarchical_select']['create_new_item']['cancel'] = array(
+    '#type' => 'button',
+    // Since "Cancel" is a common button value, we set the name property to
+    // something Drupal doesn't normally use, to prevent the form API from
+    // confusing this with other buttons on the form and choosing the wrong
+    // triggering element when the form is submitted.
+    '#name' => 'hs_select_cancel',
+    '#value' => t('Cancel'),
+    '#attributes' => array('class' => array('create-new-item-cancel')),
+    '#limit_validation_errors' => array($element['#parents']),
+    '#validate' => array(),
+    '#submit' => array('hierarchical_select_ajax_update_submit'),
+  );
+
   if (isset($element['#value']['hierarchical_select']['selects'])) {
     foreach ($element['#value']['hierarchical_select']['selects'] as $depth => $value) {
       if ($value == 'create_new_item' && _hierarchical_select_create_new_item_is_allowed($config, $depth)) {
@@ -573,11 +619,6 @@ function _hs_process_render_create_new_item($element, $hierarchy) {
           }
         }
 
-        $element['hierarchical_select']['create_new_item'] = array(
-          '#prefix' => '<div class="create-new-item">',
-          '#suffix' => '</div>',
-        );
-
         $item_type_depth = ($value == 'create_new_item') ? $depth : $depth + 1;
         $item_type = (count($config['editability']['item_types']) ==  $item_type_depth)
           ? t($config['editability']['item_types'][$item_type_depth])
@@ -595,26 +636,34 @@ function _hs_process_render_create_new_item($element, $hierarchy) {
           // Prevent the textfield from being wrapped in a div. This
           // simplifies the CSS and JS code.
           '#theme_wrappers' => array(),
-        );
-
-        $element['hierarchical_select']['create_new_item']['create'] = array(
-          '#type' => 'button',
-          '#value' => t('Create'),
-          '#attributes' => array('class' => array('create-new-item-create')),
-        );
-
-        $element['hierarchical_select']['create_new_item']['cancel'] = array(
-          '#type' => 'button',
-          '#value' => t('Cancel'),
-          '#attributes' => array('class' => array('create-new-item-cancel')),
+          // Place above "Create" / "Cancel" buttons
+          '#weight' => -1,
         );
       }
     }
   }
+  $element['hierarchical_select']['create_new_item']['#creating_new_item'] = $creating_new_item;
 
   return array($element, $creating_new_item);
 }
 
+/**
+ * <p>After-build callback for the "create_new_item" element of HS forms.</p>
+ *
+ * <p>This disables access to the add element form unless the HS widget is in
+ * create mode.
+ *
+ * @param		array	$element
+ * 								The "create_new_item" form element.
+ *
+ * @return 	array	The modified form element, with appropriate access set.
+ */
+function hierarchical_select_create_new_item_after_build(array $element) {
+  $element['#access']  = $element['#creating_new_item'];
+
+  return $element;
+}
+
 function _hs_process_render_dropbox($element, $hsid, $creating_new_item, $dropbox, $form_state) {
   $config = $element['#config'];