When a resizable frame is made non-resizable, the frame repositions itself, but the title bar do not get repainted leaving painting artifacts on screen. When a frame is repeatedly made resizable and non-resizable, the frame moves down.

To reproduce, run the below test. Repeatedly click on 'Resizable' checkbox.

This is reproducible with Ubuntu 8.04

import java.awt.*;
import java.awt.event.*;

public class Test {
    public static void main(String[] args) {
        final Frame f = new Frame();
        f.setSize(100, 100);
        f.setLayout(new FlowLayout());
        Checkbox cb = new Checkbox("Resizable", true);
        cb.addItemListener(new ItemListener() {
            public void itemStateChanged(ItemEvent event) {
                if (event.getStateChange() == ItemEvent.SELECTED) {
                    f.setResizable(true);
                } else {
                    f.setResizable(false);
                }
            }
        });
        f.add(cb);
        f.setVisible(true);
    }
}