using latest v3.0-rc6 setting log level to 'files' results in mail errors being sent from my server.
it looks as if it's trying to send the mail to the wrong variable. here's a snippet from the email:
"I'm afraid I wasn't able to deliver your message to the following addresses.
This is a permanent error; I've given up. Sorry it didn't work out.
I've seen the previous bug report with what looks to be the same issue, which says it was fixed in RC1.
either it isn't fixed, i'm doing something wrong, or this is a different bug.