As you've seen, qmail has essentially no pre-compilation configuration.You should never have to recompile it unless you want to change theqmail home directory, usernames, or uids.qmail does allow quite a bit of easy post-installation configuration. Ifyou care how your machine greets other machines via SMTP, for example,you can put an appropriate line into /var/qmail/control/smtpgreeting.But this is all optional---if control/smtpgreeting doesn't exist, qmailwill do something reasonable by default. You shouldn't worry much aboutconfiguration right now. You can always come back and tune things later.There's one big exception. You MUST tell qmail your hostname. Just runthe config-fast script:   # ./config-fast your.full.host.nameconfig-fast puts your.full.host.name into control/me. It also puts itinto control/locals and control/rcpthosts, so that qmail will acceptmail for your.full.host.name.You can instead use the config script, which looks up your host name inDNS:   # ./configconfig also looks up your local IP addresses in DNS to decide whichhosts to accept mail for.(Why doesn't qmail do these lookups on the fly? This was a deliberatedesign decision. qmail does all its local functions---header rewriting,checking if a recipient is local, etc.---without talking to the network.The point is that qmail can continue accepting and delivering local maileven if your network connection goes down.)Next, read through FAQ for information on setting up optional featureslike masquerading. If you really want to learn right now what all theconfiguration possibilities are, see qmail-control.0.