diff --git a/lib/connector/sabre/auth.php b/lib/connector/sabre/auth.php
index bf3a49593c..72ca1f8085 100644
--- a/lib/connector/sabre/auth.php
+++ b/lib/connector/sabre/auth.php
@@ -36,6 +36,8 @@ class OC_Connector_Sabre_Auth extends Sabre_DAV_Auth_Backend_AbstractBasic {
 			return true;
 		} else {
 			OC_Util::setUpFS();//login hooks may need early access to the filesystem
+			//setup extra user backends
+			OC_User::setupBackends();//if you do not want to use Owncloud's integrated login
 			if(OC_User::login($username, $password)) {
 				OC_Util::setUpFS(OC_User::getUser());
 				return true;