datewithtimezone.js

Date.prototype.stdTimezoneOffset = function() {
	var jan = new Date(this.getFullYear(), 0, 1);
	var jul = new Date(this.getFullYear(), 6, 1);
	return Math.max(jan.getTimezoneOffset(), jul.getTimezoneOffset());
}

Date.prototype.dst = function() {
	return this.getTimezoneOffset() < this.stdTimezoneOffset();
}

var d = new Date();
d.setHours(d.getUTCHours() + timezone); 
var h = d.getHours();
var m = d.getMinutes();
var s = d.getSeconds();
var ms = d.getMilliseconds();

if (d.dst()) {
	h += 1;
}