diff --git a/core/modules/toolbar/toolbar.module b/core/modules/toolbar/toolbar.module
index 6c5afb4..5c497b0 100644
--- a/core/modules/toolbar/toolbar.module
+++ b/core/modules/toolbar/toolbar.module
@@ -159,6 +159,10 @@ function toolbar_pre_render($toolbar) {
 
 /**
  * Implements template_preprocess_HOOK().
+ *
+ * The toolbar render array is built from hook_toolbar() as an array of items;
+ * each item has a tab and an optional tray. We need to separate the tabs from
+ * the trays to get the positioning to work.
  */
 function template_preprocess_toolbar(&$variables) {
   // Metadata for the toolbar wrapping element.
@@ -185,13 +189,11 @@ function template_preprocess_toolbar(&$variables) {
   $variables['trays'] = array();
   // Loop through the items. Pull out trays if defined under the #tray key.
   foreach($variables['elements']['#items'] as $key => $item) {
-    $id = drupal_html_class($key);
-    $variables['bar']['items'][$key] = $item;
-    $variables['bar']['items'][$key]['#toolbar_identifier'] = $id;
-    if (in_array('#tray', array_keys($item)) && isset($item['#tray'])) {
+    if (isset($item['#tray'])) {
       $variables['trays'][$key] = $item['#tray'];
-      $variables['trays'][$key]['#toolbar_identifier'] = $id;
+      unset($item['#tray']);
     }
+    $variables['bar']['items'][$key] = $item;
   }
   unset($variables['elements']['#items']);
 }
@@ -385,6 +387,7 @@ function toolbar_toolbar() {
 /**
  * Builds the Toolbar as a structured array ready for drupal_render().
  *
+ * @todo:  Update this doc block.
  * @return
  *   A renderable arrray, with two children:
  *   - 'tabs': an array of render elements, with default type 'link'.
@@ -416,6 +419,17 @@ function ($object) {
 
   // Get toolbar items from all modules that implement hook_toolbar().
   $toolbar_items = module_invoke_all('toolbar');
+
+  // Add properties to associate each tab with its (optional) tray.
+  foreach ($toolbar_items as $key => &$item) {
+    $id = drupal_html_class($key);
+    $item['#toolbar_identifier'] = $id;
+    if (isset($item['#tray'])) {
+      $item['#tray']['#toolbar_identifier'] = $id;
+    }
+  }
+  unset($item);
+
   // Allow for altering of hook_toolbar().
   drupal_alter('toolbar', $toolbar_items);