Java , adding minutes to a Date , weird anomaly

With Java Version 1.5.0_06 on both Windows and Ubuntu Linux :

Whenever I add minutes to the date "2008/10/05 00:00:00" , it seems that an extra hour is wrongly added.

ie: adding 360 minutes to 2008/10/05 00:00:00 at midnight should arrive at 2008/10/05 06:00:00

But it is arriving at 2008/10/05 07:00:00

The totally perplexing thing is that this ONLY happens when the day is 2008/10/05, all other days that I try perform the minutes addition correctly.

Am I going crazy or is this a bug in Java ?

    SimpleDateFormat sdf = new SimpleDateFormat("yyyy/MM/dd HH:mm:ss");

    try {
        String date = "2008/10/05 00:00:00";
        int minutesToAdd = 360;  // 6 hrs

        Calendar cal = Calendar.getInstance();
        cal.setTime(sdf.parse(date));
        cal.add(Calendar.MINUTE, minutesToAdd);
        System.out.println(cal.getTime());

    } catch (ParseException e) {}