diff --git a/uc_order/uc_order.line_item.inc b/uc_order/uc_order.line_item.inc
index e219bee..67cd778 100644
--- a/uc_order/uc_order.line_item.inc
+++ b/uc_order/uc_order.line_item.inc
@@ -128,13 +128,12 @@ function uc_order_line_item_add($order_id, $type, $title, $amount, $weight = NUL
  * Builds a list of line items defined in the enabled modules.
  */
 function _uc_line_item_list($action = NULL) {
-  static $items;
+  static $items = array();
 
   if (count($items) > 0 && $action !== 'rebuild') {
     return $items;
   }
 
-  $items = array();
   foreach (module_invoke_all('uc_line_item') as $id => $item) {
     // Preserve backward compatibility for methods with no key specified.
     if (is_numeric($id)) {