FULL PRODUCT VERSION :
Java(TM) SE Runtime Environment (build 1.6.0_07-b06)
Java HotSpot(TM) Client VM (build 10.0-b23, mixed mode, sharing)

ADDITIONAL OS VERSION INFORMATION :
Microsoft Windows XP [Version 5.1.2600]

EXTRA RELEVANT SYSTEM CONFIGURATION :
US Locale

A DESCRIPTION OF THE PROBLEM :
Windows allows users to type extended ASCII characters from the main keyboard as follows: Type control-single quote, followed by a vowel to put an accent over that vowel. control-grave accent, followed by a vowel puts an acute accent over it. control (-shift) tilde, followed by an n, a, or o puts a tilde over it. Control (-shift) colon puts an umlat over a vowel.

None of these work in java applications.

STEPS TO FOLLOW TO REPRODUCE THE PROBLEM :
1) Start with any standard Windows machine intended for USA users.

2) Open WordPad or just about any windows application (except Notepad or Firefox) and type control-single quote, e, to get the é character, just to verify that you know how to do this. Try this with other vowels, and with control-tilde, grave accent, colon, and caret (shift-6).

3) Launch the test application and try the same thing in both fields (One is a JTextField, the other is an AWT TextField.)

EXPECTED VERSUS ACTUAL BEHAVIOR :
EXPECTED -
You should be able to enter extend ASCII characters using these keystroke combinations, as you can in WordPad, Microsoft Word, and many other Windows applications.
ACTUAL -
You get characters with no diacritical marks. The control characters are ignored.

REPRODUCIBILITY :
This bug can be reproduced always.

---------- BEGIN SOURCE ----------
import java.awt.BorderLayout;
import java.awt.Component;
import java.awt.GridLayout;
import java.awt.TextField;

import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;
import javax.swing.JTextField;

public class ExtendedAsciiBug extends JPanel {

  public static void main(String[] args) {
    System.out.println( System.getProperty( "java.version" ) );
    JFrame frame = new JFrame( "Extended ASCII Bug" );
    frame.setDefaultCloseOperation( JFrame.DISPOSE_ON_CLOSE );
    frame.add( new ExtendedAsciiBug(), BorderLayout.CENTER );
    frame.pack();
    frame.setVisible( true );
  }

  public ExtendedAsciiBug() {
    super( new GridLayout( 0, 1 ) );
    addRow( "JTextField ", new JTextField( 30 ) );
    addRow( "AWT TextField ", new TextField( 30 ) );
  }

  private void addRow(String label, Component cmp) {
    JPanel panel = new JPanel( new BorderLayout() );
    panel.add( new JLabel( label ), BorderLayout.WEST );
    panel.add( cmp, BorderLayout.CENTER );
    add( panel );
  }
}

---------- END SOURCE ----------