>I'm using NetBSD 1.4.2, with standard sendmail.cf
>I've heard that there is an option called "smtp after pop" (or sth
>like that), so not everyone could use that smtp, only users that have
>account on that server.
>I think, i should make new .cf via m4, but i've read about configuring
>sendmail and haven't found that option :/

this always requires at least three things:

(1) a hack to the pop/imap server that you are using to record
authentication information for sendmail to look at.

(2) a hack to the sendmail.cf (or the corresponding mc file) to make
use of the information.

(3) a third program to maintain the database of stuff that sendmail
looks at to determine the authentication status of a given ip address.

rather than go into the intricacies of this, i'd recommend looking
into smtp-auth as another possible solution.  then your users don't
have to check their mail first in order to be allowed to send mail.

>How should my m4 file look like? I've never use m4 before.

take a look in /usr/share/sendmail/cf for examples.

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