diff --git a/services/univention-s4-connector/conffiles/etc/univention/s4connector/s4/mapping.py b/services/univention-s4-connector/conffiles/etc/univention/s4connector/s4/mapping.py
index 66f27b9f93..67aaebd2ec 100644
--- a/services/univention-s4-connector/conffiles/etc/univention/s4connector/s4/mapping.py
+++ b/services/univention-s4-connector/conffiles/etc/univention/s4connector/s4/mapping.py
@@ -30,6 +30,9 @@
 # /usr/share/common-licenses/AGPL-3; if not, see
 # <http://www.gnu.org/licenses/>.
 
+import os
+import imp
+
 import univention.s4connector.s4
 import univention.s4connector.s4.mapping
 import univention.s4connector.s4.password
@@ -1109,5 +1112,9 @@ if ignore_filter:
 		),
 }
 
-
-
+try:
+	overwrite = imp.load_source('mapping', os.path.join(os.path.dirname(__file__), 'localmapping.py')).adjustmapping
+except (IOError, AttributeError):
+	pass
+else:
+	overwrite(s4_mapping)