FULL PRODUCT VERSION :
java version "1.4.2_12"
Java(TM) 2 Runtime Environment, Standard Edition (build 1.4.2_12-b03)
Java HotSpot(TM) Client VM (build 1.4.2_12-b03, mixed mode)

ADDITIONAL OS VERSION INFORMATION :
Microsoft Windows XP [Version 5.1.2600]

A DESCRIPTION OF THE PROBLEM :
The DST offset for the EST timezone is incorrect in 1.4.2_12. The offset is correct in previous releases, tested on 1.4.2_11, 1.4.2_06, 1.4.2_04.

STEPS TO FOLLOW TO REPRODUCE THE PROBLEM :
Steps to reproduce are simple:  Get the DST for EST Timezone on 1.4.2_12 and 1.4.2_11. Observe the differences.

Or run the attached app on 1.4.2_12 and then run it on 1.4.2_11.


EXPECTED VERSUS ACTUAL BEHAVIOR :
EXPECTED -

Timezone offset between America/New_York and EST timezone is 0 sec or 0 min
Timezone America/New_York offset is -18,000,000 with DST offset 3,600,000
Timezone EST offset is -18,000,000 with DST offset 3,600,000


Timezone offset between America/Chicago and EST timezone is 3,600 sec or 60 min
Timezone America/Chicago offset is -21,600,000 with DST offset 3,600,000
Timezone EST offset is -18,000,000 with DST offset 3,600,000


Timezone offset between America/Denver and EST timezone is 7,200 sec or 120 min
Timezone America/Denver offset is -25,200,000 with DST offset 3,600,000
Timezone EST offset is -18,000,000 with DST offset 3,600,000


Timezone offset between America/Los_Angeles and EST timezone is 10,800 sec or 180 min
Timezone America/Los_Angeles offset is -28,800,000 with DST offset 3,600,000
Timezone EST offset is -18,000,000 with DST offset 3,600,000


Timezone offset between Europe/London and EST timezone is -18,000 sec or -300 min
Timezone Europe/London offset is 0 with DST offset 3,600,000
Timezone EST offset is -18,000,000 with DST offset 3,600,000


Timezone offset between Europe/Berlin and EST timezone is -21,600 sec or -360 min
Timezone Europe/Berlin offset is 3,600,000 with DST offset 3,600,000
Timezone EST offset is -18,000,000 with DST offset 3,600,000


Timezone offset between Europe/Athens and EST timezone is -25,200 sec or -420 min
Timezone Europe/Athens offset is 7,200,000 with DST offset 3,600,000
Timezone EST offset is -18,000,000 with DST offset 3,600,000



ACTUAL -

Timezone offset between America/New_York and EST timezone is -3,600 sec or -60 min
Timezone America/New_York offset is -18,000,000 with DST offset 3,600,000
Timezone EST offset is -18,000,000 with DST offset 0


Timezone offset between America/Chicago and EST timezone is 0 sec or 0 min
Timezone America/Chicago offset is -21,600,000 with DST offset 3,600,000
Timezone EST offset is -18,000,000 with DST offset 0


Timezone offset between America/Denver and EST timezone is 3,600 sec or 60 min
Timezone America/Denver offset is -25,200,000 with DST offset 3,600,000
Timezone EST offset is -18,000,000 with DST offset 0


Timezone offset between America/Los_Angeles and EST timezone is 7,200 sec or 120 min
Timezone America/Los_Angeles offset is -28,800,000 with DST offset 3,600,000
Timezone EST offset is -18,000,000 with DST offset 0


Timezone offset between Europe/London and EST timezone is -21,600 sec or -360 min
Timezone Europe/London offset is 0 with DST offset 3,600,000
Timezone EST offset is -18,000,000 with DST offset 0


Timezone offset between Europe/Berlin and EST timezone is -25,200 sec or -420 min
Timezone Europe/Berlin offset is 3,600,000 with DST offset 3,600,000
Timezone EST offset is -18,000,000 with DST offset 0


Timezone offset between Europe/Athens and EST timezone is -28,800 sec or -480 min
Timezone Europe/Athens offset is 7,200,000 with DST offset 3,600,000
Timezone EST offset is -18,000,000 with DST offset 0




REPRODUCIBILITY :
This bug can be reproduced always.

---------- BEGIN SOURCE ----------
package test;

import java.text.MessageFormat;
import java.util.Calendar;
import java.util.TimeZone;


/**
 * Test case for DST in timezone. The followin test case shows differences between JDK 1.4.2_11 and
 * JDK 1.4.2_12
 */
public class TestTimezone {

	private static Integer _int(int x) {
		return new Integer(x);
	}

	public static void test(String tz1, String tz2) {

		int utc1 = Calendar.getInstance(TimeZone.getTimeZone(tz1)).get(Calendar.ZONE_OFFSET);
		int utc2 = Calendar.getInstance(TimeZone.getTimeZone(tz2)).get(Calendar.ZONE_OFFSET);

		int utc1d = Calendar.getInstance(TimeZone.getTimeZone(tz1)).get(Calendar.DST_OFFSET);
		int utc2d = Calendar.getInstance(TimeZone.getTimeZone(tz2)).get(Calendar.DST_OFFSET);

		int result =  (utc2 + utc2d) - (utc1 + utc1d);

		System.out.println("");

		System.out.println(MessageFormat.format(
				"Timezone offset between {0} and {1} timezone is {2} sec or {3} min",
				new Object[]{   tz1, tz2, _int(result /1000), _int(result/60000)   }));

		System.out.println(MessageFormat.format(
				"Timezone {0} offset is {1} with DST offset {2}",
				new Object[] {   tz1, _int(utc1), _int(utc1d)   }));

		System.out.println(MessageFormat.format(
				"Timezone {0} offset is {1} with DST offset {2}",
				new Object[]{   tz2, _int(utc2), _int(utc2d)   }));

		System.out.println("");

	}

	public static void main(String[] args) {
		// America
		test("America/New_York", "EST");
		test("America/Chicago", "EST");
		test("America/Denver", "EST");
		test("America/Los_Angeles", "EST");

		// Europe
		test("Europe/London", "EST");
		test("Europe/Berlin", "EST");
		test("Europe/Athens", "EST");

	}

}

---------- END SOURCE ----------

CUSTOMER SUBMITTED WORKAROUND :
Do not EST timezone it is buggy.