--- a/plugins/mod_bosh.lua	Fri Apr 01 15:56:12 2016 +0200
+++ b/plugins/mod_bosh.lua	Fri Apr 01 18:56:26 2016 +0200
@@ -279,6 +279,7 @@
 			end
 			s = filter("stanzas/out", s);
 			--log("debug", "Sending BOSH data: %s", tostring(s));
+			if not s then return true end
 			t_insert(session.send_buffer, tostring(s));
 
 			local oldest_request = r[1];