diff --git a/src/Symfony/Component/Form/Extension/Core/DataTransformer/IntegerToLocalizedStringTransformer.php b/src/Symfony/Component/Form/Extension/Core/DataTransformer/IntegerToLocalizedStringTransformer.php
index dfebc1dcb3..b0fe9f6082 100644
--- a/src/Symfony/Component/Form/Extension/Core/DataTransformer/IntegerToLocalizedStringTransformer.php
+++ b/src/Symfony/Component/Form/Extension/Core/DataTransformer/IntegerToLocalizedStringTransformer.php
@@ -24,6 +24,10 @@ class IntegerToLocalizedStringTransformer extends NumberToLocalizedStringTransfo
      */
     public function reverseTransform($value)
     {
-        return (int) parent::reverseTransform($value);
+        $value = parent::reverseTransform($value);
+        if (null !== $value) {
+            $value = (int) $value;
+        }
+        return $value;
     }
 }
\ No newline at end of file