Ok, now I have in my /etc/hosts two lines:
127.0.0.1 localhost.localdomain localhost
192.168.0.90 mail.domain.com fedora
But like the mail failure says, the server is looking for localhost.localdomain...
Host or domain name not found. Name service error for
name=localhost.localdomain type=A: Host not found
Is It bad? the name should be mail.domain.com instead of localhost.localdomain no? How can I change that name?