rescuer.rb

rescue_from Exception, :with => :mail_exception

def mail_exception(exception)
	mail = Mail.new do
		from    'Rescuer (domain.com) <rescuer@domain.com>'
		to      'user@domain.com'
		subject  exception.inspect
		body     exception.backtrace[0..10].join("\n")
	end
	
	mail.delivery_method :sendmail
	mail.deliver
	
	raise exception
end