Error handling

I’m trying to create an error email notification handler that will send an email to me any time my rails app throws an exception.

I have an exception that is being thrown after redirect_to is being called and is showing the user the 500 html page.
I put these three methods in my application controller and I have log statements in all of them but none of the methods are being called.
rescue_action(exception)
rescue_action_without_handler(exception)
rescue_action_in_public(exception)

Is there another method that I need to use to rescue this exception so that I can send out an email if it is thrown?

~Kenny