There is a bug on the PC with respect to the WINDOW_ICONIFY
and WINDOW_DEICONIFY events. They are not delivered to the
frame when a window is minimized. I've attached a sample
program so you can check it out yourself.

test case:

import java.awt.*;

public class Test extends Frame {
    public boolean handleEvent(Event evt) {
switch (evt.id) {
case Event.WINDOW_ICONIFY:
case Event.WINDOW_DEICONIFY:
System.out.println("EVT: " + evt);
return true;
}
return super.handleEvent(evt);
    }

    public static void main(String argv[]) {
Test t = new Test();
t.reshape(50, 50, 100, 100);
t.show();
    }
}