I've included a simple test case below. Apparently, Australia also has a time zone know as "EST", the same id used for the US Eastern Standard Time. When an app needs to display a date/time value in Australia's "EST", it displays the date/time using the US "EST".

import java.util.*;
import java.text.*;

class Test {
    public static void main(String[] args) {
        SimpleDateFormat fm = new SimpleDateFormat("MMM d HH:mm:ss");
        fm.setTimeZone(TimeZone.getDefault());
        System.out.println("Date/time is: " + fm.format(new Date()));
    }
}