diff --git a/krebs/3modules/exim-smarthost.nix b/krebs/3modules/exim-smarthost.nix
index cee10ce7d..a01ab543b 100644
--- a/krebs/3modules/exim-smarthost.nix
+++ b/krebs/3modules/exim-smarthost.nix
@@ -136,6 +136,8 @@ let
         syslog_timestamp = false
         syslog_duplication = false
 
+        tls_advertise_hosts =
+
         begin acl
 
         acl_check_rcpt: