--- a/plugins/mod_saslauth.lua	Wed Apr 02 14:31:19 2014 +0100
+++ b/plugins/mod_saslauth.lua	Wed Apr 02 17:41:38 2014 +0100
@@ -1,7 +1,7 @@
 -- Prosody IM
 -- Copyright (C) 2008-2010 Matthew Wild
 -- Copyright (C) 2008-2010 Waqas Hussain
--- 
+--
 -- This project is MIT/X11 licensed. Please see the
 -- COPYING file in the source package for more information.
 --
@@ -242,6 +242,16 @@
 			return;
 		end
 		origin.sasl_handler = usermanager_get_sasl_handler(module.host, origin);
+		if origin.encrypted then
+			-- check wether LuaSec has the nifty binding to the function needed for tls-unique
+			-- FIXME: would be nice to have this check only once and not for every socket
+			if origin.conn:socket().getpeerfinished and origin.sasl_handler.add_cb_handler then
+				origin.sasl_handler:add_cb_handler("tls-unique", function(self)
+					return self.userdata:getpeerfinished();
+				end);
+				origin.sasl_handler["userdata"] = origin.conn:socket();
+			end
+		end
 		local mechanisms = st.stanza("mechanisms", mechanisms_attr);
 		for mechanism in pairs(origin.sasl_handler:mechanisms()) do
 			if mechanism ~= "PLAIN" or origin.secure or allow_unencrypted_plain_auth then