How to know when a preload SWF is being unloaded?

[Darrell Loverin]

This question is about the SWF loaded as a result of being specified with
the preloadSWF key. The "allComplete" event tells the preload SWF when the
application has been loaded but is there an event to tell when the
application is being unloaded so the preload SWF can flush any buffered
data?

Thanks,

-Darrell