diff --git a/flaschengeist/controller/userController.py b/flaschengeist/controller/userController.py
index 77615ba..b359d92 100644
--- a/flaschengeist/controller/userController.py
+++ b/flaschengeist/controller/userController.py
@@ -10,9 +10,15 @@ from flaschengeist import logger
 
 def login_user(username, password):
     logger.info("login user {{ {} }}".format(username))
-    try:
-        user = User.query.filter(User.userid == username).one()
-    except NoResultFound:
+    mail = username.split("@")
+    mail = len(mail) == 2 and len(mail[0]) > 0 and len(mail[1]) > 0
+
+    query = User.userid == username
+    if mail:
+        query |= User.mail == username
+    user = User.query.filter(query).one_or_none()
+    if not user:
+        logger.debug("User not found in Database.")
         user = User(userid=username)
         db.session.add(user)
     if current_app.config["FG_AUTH_BACKEND"].login(user, password):