MenuItems inside a disabled menu are traversable through keyboard and triggers action event

I have a frame with a JMenuBar and I have added few menus to the menu bar. The first menu added to the menu bar is disabled. When the frame is shown, I am pressing 'F10' and the disabled menu gets highlighted. Now I am pressing DOWN arrow key once and pressing the 'ENTER' key. The first menu item added to the disabled menu triggers an ActionEvent. This is incorrect. Disabled menus and menu items should never be accessible and should not respond to keyboard inputs.

This is noticed on solaris as well as Win32 atleast since 1.4.2.

I have attached a sample test. Run the test. Press 'F10'. Check whether the first (disabled) menu gets highlighted. Press the down arrow key once and press the 'ENTER' key. If you see an action event on the console, the bug is reproduced.