diff --git a/lib/public/iservercontainer.php b/lib/public/iservercontainer.php
index f8fa929239c444d7ce503923659dc189e9d28096..64f5f350b1ecf0a40ef4a2280fe04e75eb1b4b3b 100644
--- a/lib/public/iservercontainer.php
+++ b/lib/public/iservercontainer.php
@@ -81,9 +81,10 @@ interface IServerContainer {
 	/**
 	 * Returns a view to ownCloud's files folder
 	 *
+	 * @param string $userId user ID
 	 * @return \OCP\Files\Folder
 	 */
-	function getUserFolder();
+	function getUserFolder($userId = null);
 
 	/**
 	 * Returns an app-specific view in ownClouds data directory