diff --git a/src/Symfony/Component/Form/DataMapperInterface.php b/src/Symfony/Component/Form/DataMapperInterface.php
index 779f153835..f1867a9f90 100644
--- a/src/Symfony/Component/Form/DataMapperInterface.php
+++ b/src/Symfony/Component/Form/DataMapperInterface.php
@@ -19,8 +19,8 @@ interface DataMapperInterface
     /**
      * Maps properties of some data to a list of forms.
      *
-     * @param mixed           $data  Structured data
-     * @param FormInterface[] $forms A list of {@link FormInterface} instances
+     * @param mixed                        $data  Structured data
+     * @param FormInterface[]|\Traversable $forms A list of {@link FormInterface} instances
      *
      * @throws Exception\UnexpectedTypeException if the type of the data parameter is not supported.
      */
@@ -29,8 +29,8 @@ interface DataMapperInterface
     /**
      * Maps the data of a list of forms into the properties of some data.
      *
-     * @param FormInterface[] $forms A list of {@link FormInterface} instances
-     * @param mixed           $data  Structured data
+     * @param FormInterface[]|\Traversable $forms A list of {@link FormInterface} instances
+     * @param mixed                        $data  Structured data
      *
      * @throws Exception\UnexpectedTypeException if the type of the data parameter is not supported.
      */