Here's the thing. I've got an application that runs on WinXX platforms, but crashes on MAC OS. I'm running 1.1.8 (MRJ). Other things work find. The crash occurs when the user double clicks a button. The system freezes and you have to do a Force Quit to get out. I've tried the following: Adding a mouse listener and doing a click count. If the clickcount is greater than 1, don't execute the button's ActionPerformed. Adding a timer to execute the first click, then wait a while before accepting additional input. Setting a boolean flag in the ActionPerformed. If it is false then let the ActionListener function, otherwise don't permit the ActionPerformed from being triggered again. The button opens a dialog. I've set a boolean on in the ActionPerformed. The ActionListener can't call the ActionPerformed again until the value changes. The value is only changed in the second dialog when a user selects a button there. All these work in WinXX. All fail on the Mac. Anybody seen anything like this before?