diff --git a/src/Symfony/Component/Form/FormConfigBuilder.php b/src/Symfony/Component/Form/FormConfigBuilder.php
index 1015da4f51..391c5cd5e2 100644
--- a/src/Symfony/Component/Form/FormConfigBuilder.php
+++ b/src/Symfony/Component/Form/FormConfigBuilder.php
@@ -192,7 +192,7 @@ class FormConfigBuilder implements FormConfigBuilderInterface
     {
         self::validateName($name);
 
-        if (null !== $dataClass && !class_exists($dataClass)) {
+        if (null !== $dataClass && !class_exists($dataClass) && !interface_exists($dataClass)) {
             throw new InvalidArgumentException(sprintf('The data class "%s" is not a valid class.', $dataClass));
         }