I keep getting the "X-Authentication-Warning" in my mails where sendmail uses the -f switch for sending mails.
I have put the From header user's name in /etc/mail/trusted-users list like this:
if the email address is firstname.lastname@example.org
"email1" goes to /etc/mail/trusted-users list without the quotes.
But it doesn't help.
Does anyone know what else to do?