Bug in Calendar when setting time across daylight-saving boundaries?!

[Martin Egholm Nielsen <martin at egholm-nielsen dot dk>]

Hi there,

I was just about to tear my hear out, when I suddenly discovered that 
gcj's Calendar had some problems returning a correct Date-instance 
[getTime()] when you have changed the date of a Calendar-instance across 
the boundary of daylight-savings.
I little complicated in short terms, but consider todays date where I 
live - it's October the 2nd. Hence, we are using daylight-savings. If I 
then fetch a Calendar instance and change the month to November, the 
same day of month, and the same hour of day, I have passed the date of 
daylight savings, but then it goes wrong.
The calendar instance representing the future date calculates the 
Date-instance wrong if I invoke #getTime(). The hour of day is an hour 
short, but the day of month has suddenly gained a day - weird. Consider 
the following output from an example-application compiled with gcj 
illustrating the bug:

======== OUTPUT FROM GCJ ========
Calendar's date before: Sat Oct 02 10:30:52 GMT+02:00 2004
Calendar's date after:  Wed Nov 03 09:30:52 GMT+01:00 2004

Calendar reports hour-of-day before: 10
Calendar reports hour-of-day after:  10
Calendar's date reports hour-of-day before: 10
Calendar's date reports hour-of-day after:  9

Calendar reports day-of-month before: 2
Calendar reports day-of-month after:  2
Calendar's date reports day-of-month before: 2
Calendar's date reports day-of-month after:  3


Sun's Java returns the expected:

======== OUTPUT FROM SUN ========
Calendar's date before: Sat Oct 02 10:11:28 GMT+02:00 2004
Calendar's date after:  Tue Nov 02 10:11:28 GMT+01:00 2004

Calendar reports hour-of-day before: 10
Calendar reports hour-of-day after:  10
Calendar's date reports hour-of-day before: 10
Calendar's date reports hour-of-day after:  10

Calendar reports day-of-month before: 2
Calendar reports day-of-month after:  2
Calendar's date reports day-of-month before: 2
Calendar's date reports day-of-month after:  2


I have attached the example application.
Does anybody know if this bug has been corrected in recent libgcj's?
I've seen it with both gcj 3.3.3 and 3.4.0.

Best regards,
 Martin Egholm

import java.util.Calendar;
import java.util.Date;
import java.util.SimpleTimeZone;
import java.util.TimeZone;

public class CalendarTest {
//	private Class c = gnu.java.locale.Calendar.class;

	public static void main(String[] args) {
		// Create a timezone with daylight savings enabled from the last sunday
		// of march, and until the last sunday of october:
		SimpleTimeZone stz = new SimpleTimeZone(60 * 60 * 1000, "MyZone",
				Calendar.MARCH, -1, Calendar.SUNDAY, 2 * 60 * 60 * 1000,
				Calendar.OCTOBER, -1, Calendar.SUNDAY, 2 * 60 * 60 * 1000);

		// Register the timezone as the default:
		TimeZone.setDefault(stz);

		Calendar cal = Calendar.getInstance();
		Date calendarsDateBefore = cal.getTime();
		System.out.println("Calendar's date before: " + calendarsDateBefore );

		// Let's store the hour-of-day and day of month for later:
		int hourOfDayBefore = cal.get(Calendar.HOUR_OF_DAY);
		int dayOfMonthBefore = cal.get(Calendar.DAY_OF_MONTH);

		int changeMonthTo;

		// Let's test if our current date is in the dst-area:
		if (stz.inDaylightTime(cal.getTime())) {
			changeMonthTo = Calendar.NOVEMBER;
		} // if
		else {
			changeMonthTo = Calendar.APRIL;
		} // else

		// Set the month to a month with different dst-settings that the one
		// we're in now:
		cal.set(Calendar.MONTH, changeMonthTo);

		// Specifically set the hour of day and day of month to the same as
		// before:
		cal.set(Calendar.HOUR_OF_DAY, hourOfDayBefore);
		cal.set(Calendar.DAY_OF_MONTH, dayOfMonthBefore);

		Date calendarsDateAfter = cal.getTime();
		System.out.println("Calendar's date after:  " + calendarsDateAfter );

		int hourOfDayAfter = cal.get(Calendar.HOUR_OF_DAY);
		int dayOfMonthAfter = cal.get(Calendar.DAY_OF_MONTH);
		
		System.out.println();
		System.out.println("Calendar reports hour-of-day before: "
				+ hourOfDayBefore);
		System.out.println("Calendar reports hour-of-day after:  "
				+ hourOfDayAfter);
		System.out.println("Calendar's date reports hour-of-day before: "
				+ calendarsDateBefore.getHours());
		System.out.println("Calendar's date reports hour-of-day after:  "
				+ calendarsDateAfter.getHours());

		System.out.println();

		System.out.println("Calendar reports day-of-month before: "
				+ dayOfMonthBefore);
		System.out.println("Calendar reports day-of-month after:  "
				+ dayOfMonthAfter);
		System.out.println("Calendar's date reports day-of-month before: "
				+ calendarsDateBefore.getDate());
		System.out.println("Calendar's date reports day-of-month after:  "
				+ calendarsDateAfter.getDate());
	} // main
} // CalendarTest