Refusing users without a mailbox?

[Dmitriy Kirhlarov]

Paul van der Vlis wrote:
> Hello,
> 
> A customer is using a system with a mailserver and a FTP-server on one
> machine.
> 
> Now a FTP-user found out, that he can login with his FTP-username and
> password into the webmail (Horde/IMP), and send mail.
> 
> FTP-users do not have a mailbox. Is there a way to make the
> authentication "not OK" for users without a mailbox?
> Or only "OK" for users who are member of a group?
> 
> I am using Cyrus with saslauthd, PAM and the traditional Unix
> authentication mechanism (pam_unix.so).

Look like you need:
http://www.splitbrain.org/projects/pam_require/

WBR.
Dmitriy