diff --git a/src/Symfony/Bundle/FrameworkBundle/Resources/config/serializer.xml b/src/Symfony/Bundle/FrameworkBundle/Resources/config/serializer.xml
index 61a6e66653cb2..04a6caed4a905 100644
--- a/src/Symfony/Bundle/FrameworkBundle/Resources/config/serializer.xml
+++ b/src/Symfony/Bundle/FrameworkBundle/Resources/config/serializer.xml
@@ -16,11 +16,14 @@
+
+
null
+