diff -r 000000000000 -r 7f95f8617b0b vendor/symfony/src/Symfony/Component/Form/CallbackValidator.php
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/vendor/symfony/src/Symfony/Component/Form/CallbackValidator.php	Sat Sep 24 15:40:41 2011 +0200
@@ -0,0 +1,29 @@
+<?php
+
+/*
+ * This file is part of the Symfony package.
+ *
+ * (c) Fabien Potencier <fabien@symfony.com>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace Symfony\Component\Form;
+
+class CallbackValidator implements FormValidatorInterface
+{
+    private $callback;
+
+    public function __construct($callback)
+    {
+        // TODO validate callback
+
+        $this->callback = $callback;
+    }
+
+    public function validate(FormInterface $form)
+    {
+        return call_user_func($this->callback, $form);
+    }
+}