diff --git a/ejabberd/templates/ejabberd.yml.erb b/ejabberd/templates/ejabberd.yml.erb
index cc3a667..984be7d 100644
--- a/ejabberd/templates/ejabberd.yml.erb
+++ b/ejabberd/templates/ejabberd.yml.erb
@@ -150,6 +150,7 @@ modules:
   mod_blocking: {}
   mod_caps: {}
   mod_carboncopy: {}
+  mod_client_state: {}
   mod_configure: {}
   mod_disco: {}
   mod_http_bind: {}