while using postfix, i can't select user@domain as format for new users:
"The Module Config option Format for usernames that include domain is set to username@domain, which is only supported by Sendmail."
But this is actually not true, as i have a perfectly good working setup - if i rename users from user-domain.tld to firstname.lastname@example.org and update the virtal map.
I'm using a simple postfix install w/ sasl->pam authentication.
IMHO, this error(?!?) should not exist or at least be a warning but let it work anyway.