--- a/plugins/muc/members_only.lib.lua	Wed Oct 15 16:56:42 2014 -0400
+++ b/plugins/muc/members_only.lib.lua	Wed Oct 15 17:07:16 2014 -0400
@@ -20,6 +20,30 @@
 	members_only = members_only and true or nil;
 	if room._data.members_only == members_only then return false; end
 	room._data.members_only = members_only;
+	if members_only then
+		--[[
+		If as a result of a change in the room configuration the room type is
+		changed to members-only but there are non-members in the room,
+		the service MUST remove any non-members from the room and include a
+		status code of 322 in the presence unavailable stanzas sent to those users
+		as well as any remaining occupants.
+		]]
+		local occupants_changed = {};
+		for nick, occupant in room:each_occupant() do
+			local affiliation = room:get_affiliation(occupant.bare_jid);
+			if valid_affiliations[affiliation or "none"] <= valid_affiliations.none then
+				occupant.role = nil;
+				room:save_occupant(occupant);
+				occupants_changed[occupant] = true;
+			end
+		end
+		local x = st.stanza("x", {xmlns = "http://jabber.org/protocol/muc#user"})
+			:tag("status", {code="322"}):up();
+		for occupant in pairs(occupants_changed) do
+			room:publicise_occupant_status(occupant, x);
+			module:fire_event("muc-occupant-left", {room = room; nick = occupant.nick; occupant = occupant;});
+		end
+	end
 	if room.save then room:save(true); end
 	return true;
 end