diff --git a/UI/SOGoUI/SOGoACLAdvisory.m b/UI/SOGoUI/SOGoACLAdvisory.m
index 78a146e5c..40cc8d0bb 100644
--- a/UI/SOGoUI/SOGoACLAdvisory.m
+++ b/UI/SOGoUI/SOGoACLAdvisory.m
@@ -86,6 +86,7 @@
 {
   NSMutableString *url;
 
+#warning the url returned by SOGoMail may be empty, we need to handle that
   url
     = [NSMutableString stringWithString:
 			 [aclObject httpURLForAdvisoryToUser: recipientUID]];