So siehts ganz gut aus !

node_modules/es5-ext/date/is-date.js

@@ -0,0 +1,10 @@
+"use strict";
+
+var objToString = Object.prototype.toString, id = objToString.call(new Date());
+
+module.exports = function (value) {
+	return (
+		(value && !isNaN(value) && (value instanceof Date || objToString.call(value) === id)) ||
+		false
+	);
+};