The ability manipulate the Quit button and process Quit events

Currently Izpack has the following limitations:
a) You cannot hide or disable the Quit button on the InstallerFrame. In our scenario we have optional panels for rollback if anything should fail during installation and we definitively don't want the user to be able to Quit before we can do rollback.
b) The Quit button doesn't allow custom handling of events. If a user chooses yes, I would like to be able to veto his decision and do different processing like displaying a message, or just add some logic to the quit process.

Please give panels access to the quit button and also the ability process the quit events.