FC4 & pop users for sendmail

[C.F. Scheidecker Antunes]

Hello All,

I 've always used Linuxconf since RH 5.2.
In fact, I like Linuxconf just for two small reasons. First to adjust 
date and time as it is easy, and second, for sendmail servers it is nice
to create "popusers". That is, Linuxconf creates a group and users 
popusers that can only get and retrieve email. They cannot access the 
system remotely or do any other thing.
However, after it was removed things got difficult.

All my sendmail configuration I like to do with a editor like emacs and 
vi. I prefer to have control of all my configurations other than having 
an app doing for me. But for the pop users, Linuxconf was nice to have.

Therefore, the help I need is: How to create users that can only access 
email messages from a Linuxbox?

I appreciate all insights and advices on this.

Thanks,

C.F.