Reproducible using DitherTest demo applet. To reproduce:
* click on the Horizontal or Vertical Choice to pop id down (this part can't be done w/ b84 - you need to use b80 or before)
* with the Choice still popped down, click on the New Image button

This causes the dithered image to be updated, but it shouldn't.

Problems:
* in 1.3.1, clicking on the button w/ the Choice popped down would only cause the Choice to pop back up, NOT cause the image to be updated
* when the button is clicked, the button is not painted as "depressed", even though an ActionEvent is apparently still fired.