Popup Modal dialog in Java Plugin is not behaving like true Modal Dialog solaris

Pop up AWT dialogs are not behaving like true Modal Dialogs
in a browser(Netscape 4.X and Netscape 6 ) using Java Plugin Merlin Build 50.

Any of the Menu's in the browser are accessable when a modal
Dialog is popup .This is not a true modal dialog box behaviour the user
should not able to access any thing in the browser until the
repose is given to the Modal Dialod.

Also , all the Buttons are not dispalyed in the browser.In the test cases
"show modal dialog" and "Set Color to Red" are the 2 buttons but
only "show modal dialog" button is shown.The other one is not shown in the
browser.This behaviour is not same on Windows.,

The Swing Modal Dialog Box is throwing the exception when selected (Please find attachment exception message in console)

To reproduce the Problem :

1. Install Java Plugin Merlin Build 50
2. Run the test case 6 a and 6 b from the
   following location.
 (Please see attached is the Exception message display in the console
  when trying to run 6a)
3.Run 6b , click on the show dialog button
  (you can see only one button displayed instead of 2 buttons in the
   test case)
4. Any of the menus in the browser can be selected when the Modal Dialog is still poped up.

URL for the Test cases :

http://sqesvr.eng.sun.com/deployment1/ws/doc/proc/JPI_AUE.html

Or Run the test cases from :

1.
      http://sqesvr.eng.sun.com/deployment2/sridhare/ws-07-2000/tests/applet_usability/modal_dialog/TestSwingModal.html

2.
http://sqesvr/deployment2/sridhare/ws-07-2000/tests/applet_usability/modal_dialog/AWTModalTest.html