diff --git a/lib/Doctrine/DBAL/Types/ConversionException.php b/lib/Doctrine/DBAL/Types/ConversionException.php
index 7c47286faf453d30a0cef059860ee7fc0a54fbad..5f91cc308e4bab921a9e8877af36c8739a488d89 100644
--- a/lib/Doctrine/DBAL/Types/ConversionException.php
+++ b/lib/Doctrine/DBAL/Types/ConversionException.php
@@ -100,7 +100,7 @@ class ConversionException extends \Doctrine\DBAL\DBALException
         ));
     }
 
-    static public function conversionFailedSerialization($value, $format, $error, \Exception $previous = null)
+    static public function conversionFailedSerialization($value, $format, $error)
     {
         $actualType = is_object($value) ? get_class($value) : gettype($value);