tcpserver unable to figure out port number for smtp

[Fish Flowers]

OK, I lied, qmail is logging -- I just wasn't clueful enough to figure out
where. But now I have! (Thanks James and Charles.) But it didn't help.
/var/log/qmail/smtpd/current shows the following:

@400000003a71e0a43872189c tcpserver: fatal: unable to figure out port
number for smtp
... repeat ad nauseam

OK, fair enough... how do I open the port? Or point tcpserver to
it? Ack! Lack of unix training coming back to bite me in the butt!

Fish.