Focus Traversal Issue when a button is disabled via a a control on a different stage

In my test UI I have 2 stages. Stage 1 has a button and a rectangle. Button's action function prints some statements on the command line. Stage 2 has a checkbox and clicking on this checkbox causes the button to be disabled.
Steps to reproduce bug:
1)Click on Button\Press SpaceBar - It prints the value of the button's disable attribute on command line - this is as expected since button is currently enabled.
2)Now select the swingcheckbox in stage 2 - this will disable the button.
3)Click on stage1 to make it the active window.
4)Now press SpaceBar- the print statements appear at command prompt - indicating that the button still has focus even though it has been disabled.