On Sun, 2010-12-12 at 21:08 +0100, Agim Cami wrote:

What will be the right authentication scheme for a mail system with Microsoft Outlook as client and shadow passwords for Linux system users?

http://wiki.dovecot.org/Authentication

Only PLAIN authentication mechanism works for passwords in /etc/shadow.

The password scheme doesn't matter, but you don't have many choices when your passwords are in /etc/shadow.

It makes no difference that you're using Outlook.