Postfix supports the operation of the Linux postfix mail server based on MySQL. TYPO3 administers are enabled to manage the accounts of their users with the table fe_users. Other tables enable to configure forwarding, masquerading and auto-responding. You can provide a third party webmailer like Roundcube.
A tutorial in German language presents the installation and configuration of postfix, courier and roundcube on a Linux web-server.
The manual has 15 pages, the Tutorial has 26 pages.