Weird Date Calc error

[xtrememenace]

Hello,

I'm getting a weird error, if I enter the date like this,

var _date = new Date();
_date.setMonth(9);
_date.setDate(20);
_date.setHours(02);
_date.setMinutes(00);
_date.setSeconds(00);
$('#counter').countdown({
startTime: _date,
image: "img/digits.png"
});
The output should be 69:21:15:45.... But I'm getting the output as 69:09:15:45.. It seems the Hours value is either not in a 24-hr format or is being wrongly calculated...
Could some1 help me on this??