Please see attched image file.
Mnemonic Keys which was mistaken on the Japanese
is attached.

To reproduce:

[case1] 
1.New -> GUI Forms -> JFrame.
  JFrame is created. 
  Form Editor displays.
2.JButton of Swing is added to Form.
3.JButton is moved to the North.
4.Connection Mode is chosen, JButton is pushed
  and, next, it pushes except JButton.
  Connection Wizard displays.
  ---The Mnemonic Keys of "Method Name:"
     (Image1-1.gif,Image1-2.gif).

[case2]
1.Right click is carried out on Pallet and 
  Create New Category is chosen.
  New Palette Category displays.
  ---The Mnemonic Keys of "New Category Name:"
     (Image2.gif).

[case3]
1.Right click is carried out on Category
  and Rename is chosen.
  Rename displays.
  ---The Mnemonic Keys of "New Category Name:"
     (Image3.gif).

Would you check if the first character is not used
as mnemonic key?
By localization, the first character becomes
no-ascii character. As a result, the mnemonic key
doesn't work by localization. To fix this
problem, we need to set two resource bundle
messages, one is for caption, another is for
mnemonic.
       Example=TestString
       Example_Mnemonic=T

And we should use like this:   
myButton.setText(myBundle.getString("Example"));  
myButton.setMnemonic(myBundle.getString("Example_Mnemonic").charAt(0).

The following line does not work with localized
version, because the
first character is not an alphanumeric because
it's replaced to multi-byte Japanese character.

myButton.setMnemonic(myResourceBundle.getString("Example").charAt(0));

*OS:Solaris 8  
*Orion Build:orion_020507
*JDK:JDK1.4.0
*locale:ja