Email Certification?

Hum. Can anyone figure out a way to determine if one's hotmail, etc...has been looked at or not? The only thing my limited mind can think of sounds superficially like it won't work: Use a gmail account to forward all email to some routine that time-stamps and then hashes the message+timestamp and then sends the email on to the hotmail account. Of course, "they" can just start looking at the gmail account and monkey with things before they get over to the hotmail account. But that might be an improvement...depending on how gmail forwards, they might not be able to interfere without at least notifying gmail. That's a lot better than nothing. -TD