--- a/plugins/muc/muc.lib.lua	Sun Jan 26 21:16:24 2014 +0100
+++ b/plugins/muc/muc.lib.lua	Tue Jan 28 19:21:21 2014 +0100
@@ -570,6 +570,7 @@
 				end
 				stanza.attr.from, stanza.attr.to, stanza.attr.id = from, to, id;
 			else -- message
+				stanza:tag("x", { xmlns = "http://jabber.org/protocol/muc#user" }):up();
 				stanza.attr.from = current_nick;
 				for jid in pairs(o_data.sessions) do
 					stanza.attr.to = jid;