diff --git a/src/Symfony/Component/HttpFoundation/Request.php b/src/Symfony/Component/HttpFoundation/Request.php
index b609f66d5c..6fd93e9093 100644
--- a/src/Symfony/Component/HttpFoundation/Request.php
+++ b/src/Symfony/Component/HttpFoundation/Request.php
@@ -382,7 +382,7 @@ class Request
      * to keep BC with an existing system. It should not be used for any
      * other purpose.
      *
-     * @param callable $callable A PHP callable
+     * @param callable|null $callable A PHP callable
      */
     public static function setFactory($callable)
     {
diff --git a/src/Symfony/Component/HttpFoundation/Tests/RequestTest.php b/src/Symfony/Component/HttpFoundation/Tests/RequestTest.php
index 6b378a1f9e..9d1dcbe441 100644
--- a/src/Symfony/Component/HttpFoundation/Tests/RequestTest.php
+++ b/src/Symfony/Component/HttpFoundation/Tests/RequestTest.php
@@ -1634,6 +1634,8 @@ class RequestTest extends \PHPUnit_Framework_TestCase
         });
 
         $this->assertEquals('foo', Request::create('/')->getFoo());
+
+        Request::setFactory(null);
     }
 }