You're absolutely right -- that is really dumb. I would have sworn it was on Mozy's site, but I guess I only remember that from reading external reviews as you say.Lovely how that's not listed as a requirement anywhere on Mozy's site, except in links to external reviews mentioning it.
I have 41 GB backed up. If i wanted to change to a custom key, do i have to back up all my stuff again? I'd really like to see if the custom key restore works or not on my machine.