Using ckpasswd -s to authenticate users

[Jeffrey Davis]

Ok, now that I have this news server up, running and allowing posts and
reads...
I want to restrict its use to only those users that have an account on my
server (with RedHat I guess this means I need to authenticate with shadow
passwords).

In reading the man page for reader.conf it says:
"note that ckpasswd may have to be setgid to a shadow group to use this
option"

What does this mean? I thought that all the programs in ~/news/bin had to be
chown to news:news

This is what I have that works:
auth "Users" {
        hosts: "*"
        default: <local>
}
access "Users" {
        newsgroups: "*, !junk, !control, !control*"
}
 (obviously it works... It lets anyone in!)

This is what I tried that didn't work:
It still lets anyone in

auth "Users" {
        hosts: "*"
        auth: "ckpasswd -s"
        default: <local>
}
access "Users" {
        newsgroups: "*, !junk, !control, !control*"
}