Qmail Configuration: /var/qmail/control & qmail-control

me

my host name (default for many other options)

locals

Host names for which we do local delivery

rcpthosts

Host names for which we receive mail

envnoathost

Appended if address lacks '@'

virtualdomains

sockerfans.org:rossi, .fax:uucp-fax

badmailfrom

denied envelope senders (@spam.com)

There are many other configuration items. Start with "man qmail-control".