--- a/plugins/mod_pubsub/pubsub.lib.lua	Sat Sep 01 03:01:55 2018 +0200
+++ b/plugins/mod_pubsub/pubsub.lib.lua	Sat Sep 01 03:02:44 2018 +0200
@@ -71,6 +71,7 @@
 	};
 	{
 		type = "text-single";
+		datatype = "xs:integer";
 		name = "max_items";
 		var = "pubsub#max_items";
 		label = "Max # of items to persist";