OnBlur not firing from Html edit mode

      function OnClientLoad(editor, args) {
            editor.set_mode(2);

            var element = document.all ? editor.get_document().body : editor.get_document();
            $telerik.addExternalHandler(element, "blur", function (e) {            
                alert("RadEditor lost focus");
            });

            editor.attachEventHandler("blur", function (e) {
                alert("Blur fired");
            });

        }