--- a/plugins/mod_s2s/mod_s2s.lua	Sun Oct 07 20:58:51 2018 +0200
+++ b/plugins/mod_s2s/mod_s2s.lua	Mon Oct 08 15:03:26 2018 +0200
@@ -81,7 +81,7 @@
 		local reply = data[2];
 		if reply and not(reply.attr.xmlns) and bouncy_stanzas[reply.name] then
 			reply.attr.type = "error";
-			reply:tag("error", {type = "cancel"})
+			reply:tag("error", {type = "cancel", by = session.from_host})
 				:tag("remote-server-not-found", {xmlns = "urn:ietf:params:xml:ns:xmpp-stanzas"}):up();
 			if reason then
 				reply:tag("text", {xmlns = "urn:ietf:params:xml:ns:xmpp-stanzas"})