diff --git a/templates/bootstrap/bootstrap-panel.vars.php b/templates/bootstrap/bootstrap-panel.vars.php
index 685b67a..2624c46 100644
--- a/templates/bootstrap/bootstrap-panel.vars.php
+++ b/templates/bootstrap/bootstrap-panel.vars.php
@@ -57,5 +57,7 @@ function bootstrap_preprocess_bootstrap_panel(&$variables) {
  * Implements hook_process_bootstrap_panel().
  */
 function bootstrap_process_bootstrap_panel(&$variables) {
-  $variables['attributes'] = drupal_attributes($variables['attributes']);
+  if (is_array($variables['attributes'])) {
+    $variables['attributes'] = drupal_attributes($variables['attributes']);
+  }
 }