NSInvalidArgumentException error in simple email application for iPad

Question

I am trying to prepare a simple application to send an e-mail.

I was using this example: http://blancer.com/tutorials/i-phone/76884/mail-send-from-ipad/

but, I am getting an error running the application on the iPad device. It works perfectly fine on the iPad simulator.

The line of code it is crashing:

[self presentModalViewController:mailController animated:YES];

with this error:

Terminating app due to uncaught exception 'NSInvalidArgumentException', reason: 'Application tried to present a nil modal view controller on target

Thank you for your help