Here is an example showing a different behaviour with numpad between jdk 1.1.4
for winNT 4.0 and jdk 1.1.4 for solaris 2.5.1.

% cat MyTextField.java
import java.awt.*;
import java.awt.event.*;

public class MyTextField extends TextField {

protected void processKeyEvent( KeyEvent k ) {
String s="K ";
           if (k.getKeyCode()==KeyEvent.VK_NUMPAD1){
              s+=" VK_NUMPAD1 ";
           }else if (k.getKeyCode()==KeyEvent.VK_END){
              s+=" VK_END ";
           }
           if (k.getKeyCode()==KeyEvent.VK_NUMPAD0){
              s+=" VK_NUMPAD0 ";
           }else if (k.getKeyCode()==KeyEvent.VK_INSERT){
              s+=" VK_INSERT ";
           }
           s+="<"+k.getKeyCode()+"> "+k.getKeyChar();
           System.out.println(s);
}

public MyTextField() {
enableEvents(AWTEvent.KEY_EVENT_MASK);
}

public static void main( String[] args ) {
Frame f = new Frame();
f.setSize( 200, 100 );
f.add( new MyTextField() );
f.show();
}
}
%

Under solaris 2.5.1, with or without NumLock pressed, the keycode of a numpoad
key is the same.
Under winNT, there is a difference if NumLock is pressed or not.

Example of output for the key "8" :

Under Solaris :
without or with NumLock, we've got K <38>

Under WinNT :
without NumLock, we've got K <38>
but with NumLock, we've got K <104>