Warning: you still need to edit myorigin/mydestination/mynetworks
parameter settings in /etc/postfix/main.cf.
See also http://www.postfix.org/STANDARD_CONFIGURATION_README.html
for information about dialup sites or about sites inside a firewalled
network.
BTW: Check your /etc/aliases file and be sure to set up aliases
that send mail for root and postmaster to a real person, then run
/usr/bin/newaliases.