function daylightSaving()
{
    var now = new Date(),
       nowTZ = now.getTimezoneOffset(),
       winterTZ = new Date(now.getFullYear(), 1, 1).getTimezoneOffset(),
       summerTZ = new Date(now.getFullYear(), 7, 1).getTimezoneOffset();
    return (winterTZ !== summerTZ) && (nowTZ === summerTZ) ? 1 : 0;

}
function calculate_time_zone(offset)
{
    offset += daylightSaving();
    var d = new Date();
    var utc = d.getTime() + (d.getTimezoneOffset() * 60000);
    var rightNow = new Date(utc + (3600000 * offset));
    return convert(rightNow);
}
function padZero(n)
{
    n = "00" + n;
    return n.substring(n.length - 2);
}
function convert(value) 
{
	return padZero(value.getHours()) + ":" + padZero(value.getMinutes());
}