E-Check has cleared Email?

Is it possible to setup a system that sends out an email saying that an echeck has cleared? I see that now (unlike before), a cleared check somehow is notified to zencart, and it automatically processes the order at that point, but there is no notification. As a seller of Downloads, it's important to notify the cusomer that their order has processed, and that they can now download their purchase. Is there a way (or can a way be easily added) to send a notice?

Edit: PS: this is with the Paypal IPN module; neither the express nor pro are installed for me.

Can anyone at least point in the direction of the code that processes cleared echecks so that I can find the spot where email code should go?

I'd probably start with ipn_main_handler.php and related function files in the paypal payment module folder

Thanks. I think I got it (I hope).