public void testRemoveOOBMessage() {
NakReceiverWindow win=new NakReceiverWindow(sender, cmd, 0, timer);
System.out.println("win = " + win);
win.add(2, new Message());
System.out.println("win = " + win);
assertNull(win.removeOOBMessage());
assertNull(win.remove());
win.add(1, oob());
System.out.println("win = " + win);
assertNotNull(win.removeOOBMessage());
System.out.println("win = " + win);