diff --git a/lib/Doctrine/ORM/Internal/CommitOrderCalculator.php b/lib/Doctrine/ORM/Internal/CommitOrderCalculator.php
index b5153e6d3..9e069b0e3 100644
--- a/lib/Doctrine/ORM/Internal/CommitOrderCalculator.php
+++ b/lib/Doctrine/ORM/Internal/CommitOrderCalculator.php
@@ -62,7 +62,7 @@ class CommitOrderCalculator
      */
     public function clear()
     {
-        $this->_classes =
+        $this->_classes = array();
         $this->_relatedClasses = array();
     }