X-Authentication-Warning
 

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 email1@domain.com then
"email1" goes to /etc/mail/trusted-users list without the quotes.

But it doesn't help.

Does anyone know what else to do?

TIA.