I've resolved the problem by placing the booleanCheckbox inside a panel. Set the panel to prevent the event from bubbling up instead of setting it on the checkbox component itself.
good to hear that resolved.
General advice according to your code snippets. It's RichFaces 3.3.3 limitation that you can't use a4j:support for component event and the js handler for the same event in the same time. event ha dler will rewrite support call.