FULL PRODUCT VERSION :
java version "1.6.0-rc"
Java(TM) 2 Runtime Environment, Standard Edition (build 1.6.0-rc-b66)
Java HotSpot(TM) Client VM (build 1.6.0-rc-b66, mixed mode, sharing)

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

EXTRA RELEVANT SYSTEM CONFIGURATION :
Windows "Text Services and Input Languages" settings:
language=Finnish, keyboard=Finnish

A DESCRIPTION OF THE PROBLEM :
In the finnish keyboard, one should be able to input a tilde character (~) with the following key sequence: <alt gr>+<tilde>, <space>.

I.e. <alt gr>+<title> is dead key combination, which can also be used to produce characters such as a with tilde (ã, produced with <alt gr>+<tilde>, <a>) and n with tilde (ñ, produced with <alt gr>+<tilde> <a>), etc.

This bug has previously been reported as 4957565, but that has been closed as resolved in b40. Obviously the resolution has not been tested because the bug persists.

Also I would like to note that the bug is in the 1.5.0_06 and needs to be fixed fast.

STEPS TO FOLLOW TO REPRODUCE THE PROBLEM :
1. Get a Finnish keyboard (if available, otherwise see instructions at the end)
2. Change the keyboard layout to Finnish in XP (for instructions see http://www.microsoft.com/globaldev/handson/user/xpintlsupp.mspx)
3. Launch any Java application with a AWT TextField or Swing JTextField
4. Set focus to the TextField
5. Press simultaneously the "Alt Gr" button and the button with tilde (~) on it. Release.
6. Press space
7. Repeat 6
8. Press "a"

Note: on Finnish keyboard, the button with tilde (~) has also the acute (^) and the diaeresis (¨), the button is located just left to enter, at the same location where the button with } and ] is on the UK keyboard. See also http://en.wikipedia.org/wiki/Keyboard_layout for a picture of the layout.

EXPECTED VERSUS ACTUAL BEHAVIOR :
EXPECTED -
Step 5 should not produce any character
Step 6 should produce the lone character tilde (~)
Step 7 should not produce any character
Step 8 should produce the lone character a with tilde (ã)
ACTUAL -
Step 5 does not produce anything (as expected)
Step 6 produces a space
Step 7 does not produce anything (as expected)
Step 8 produces the character "a"

REPRODUCIBILITY :
This bug can be reproduced always.

---------- BEGIN SOURCE ----------
import java.awt.*;

public class TildeTest {
  public static void main(String[] args) {
    Frame f = new Frame();
    f.add(new TextField());
    f.pack();
    f.setVisible(true);
  }
}
---------- END SOURCE ----------

CUSTOMER SUBMITTED WORKAROUND :
There is no proper workaround.

The tilde character can be produced on the Finnish keyboard with the following key sequence: <tilde>, <alt gr>+<tilde>. This will produce the characters diaeresis (¨) and tilde (~), after which one can delete the unwanted diaeresis away.

However, the above workaround does not allow typing in any of the tilde characters, such as a with tilde (ã) or n with tilde (ñ).