diff --git a/SoObjects/Appointments/SOGoAppointmentObject.m b/SoObjects/Appointments/SOGoAppointmentObject.m
index bcd85d6b7..d85463383 100644
--- a/SoObjects/Appointments/SOGoAppointmentObject.m
+++ b/SoObjects/Appointments/SOGoAppointmentObject.m
@@ -553,7 +553,7 @@
               
           values = [NSDictionary dictionaryWithObjectsAndKeys:
                                    [user cn], @"Cn",
-                                 [user systemEmail], @"SystemEmail"];
+                                 [user systemEmail], @"SystemEmail", nil];
           reason = [values keysWithFormat: [self labelForKey: @"Cannot access resource: \"%{Cn} %{SystemEmail}\""]];
           return [NSException exceptionWithHTTPStatus:403 reason: reason];
         }