My MythTV setup crashed a 2-3 times per week for several months. I eventually discovered that it was the Linux driver for my StreamZap LIRC receiver. I replaced it with a serial-based receiver, and haven't had a crash since.

What I'm saying, it's probably a hardware/driver problem, not a MythTV problem.

It really is what's called the "envelope sender". In the SMTP protocol, you have to specify who the message is from, and what addresses to deliver to. These don't necessarily have any relation to the From: and To: headers in the message itself.

I have noticed the same thing you have, I believe that the envelope sender is the correct person to contact.