Should it be possible to send e-mail to addresses like
root(a)wikipedia.org, postmaster(a)wikipedia.org, etc? At the
moment, sendmail doesn't accept connections except from
the local machine on loopback so, eg a theoretical person
trying to complain about a spammer sending stuff through
clever manipulation of the "e-mail this user" function
couldn't reach the customary addresses.
I'm sure it's just a matter of sendmail configuration; I'm
just not very up on that because I use qmail on my server.