FULL PRODUCT VERSION :
SE Runtime Environment (build 1.6.0_03-b05)
Java HostSpot Client VM (build 1.6.0_03-b05, mixed mode)

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

A DESCRIPTION OF THE PROBLEM :
Calling getOffset() on a TimeZone Object, on Feb. 29, causes an java.lang.IllegalArgumentException at sun.util.calendar.ZoneInfo.getOffset(Unknown Source)

STEPS TO FOLLOW TO REPRODUCE THE PROBLEM :
1) Set system date to Feb. 29, 2008
2) Sample Code:
            long elasped = (System.currentTimeMillis() - <a time prior to now>
            elasped = elasped -
                    today.getTimeZone().getOffset(today.ERA,
                    today.get(Calendar.YEAR), today.get(Calendar.MONTH),
                    today.get(Calendar.DATE), today.get(Calendar.DAY_OF_WEEK),
                    0);

EXPECTED VERSUS ACTUAL BEHAVIOR :
EXPECTED -
It should not fail.
ACTUAL -
Results in java.lang.IllegalArgumentException at sun.util.calendar.ZoneInfo.getOffset(Unknown Source)

REPRODUCIBILITY :
This bug can be reproduced always.

---------- BEGIN SOURCE ----------
import java.util.*;
public class LeapYearDemo {
    public static void main(String[] args) {
        Date aDate = new Date();
        Calendar today = Calendar.getInstance();
        long elasped = (System.currentTimeMillis() - aDate.getTime());
        elasped = elasped -
                today.getTimeZone().getOffset(today.ERA,
                today.get(Calendar.YEAR), today.get(Calendar.MONTH),
                today.get(Calendar.DATE), today.get(Calendar.DAY_OF_WEEK),
                0);
        System.out.println(elasped);
    }
---------- END SOURCE ----------