Action events not firing in JCombox's selected item

FULL PRODUCT VERSION :
java version "1.5.0_11"
Java(TM) 2 Runtime Environment, Standard Edition (build 1.5.0_11-b03)
Java HotSpot(TM) Client VM (build 1.5.0_11-b03, mixed mode)

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

A DESCRIPTION OF THE PROBLEM :
I recently updated to version 1.6 of the JRE. I have several applications build using Netbeans 5.5 and compiled using java version 1.5.0. After upgrading to version 1.6 The action events for JComboBox, JTextField and JButton do not fire. These are the only action events I tested so there may be others as well that do not respond to a mouse click or pressing the "Enter" Key.

STEPS TO FOLLOW TO REPRODUCE THE PROBLEM :
Install java jre version 1.6 then execute an application build using Swing components that have action events associated with them and compiled using java jdk 1.5. Select an item from a JComboBox, click on a JButton or press the enter key when the cursor is in a JTextField.

EXPECTED VERSUS ACTUAL BEHAVIOR :
EXPECTED -
I expected the application to work just like it did using jre version 1.5. All events should have fired and executed the event handlers attached to the above described objects.
ACTUAL -
None of the action events fired or executed the event handler code assigned to the objects in question.

REPRODUCIBILITY :
This bug can be reproduced always.

Release Regression From : 5.0u11
The above release value was the last known release where this
bug was not reproducible. Since then there has been a regression.