What features are not provided by Exim?

Exim is designed to move messages from one e-mail server to another and to deliver messages to local users mailboxes. Features such as POP3, IMAP, shared calendars, address books and group scheduling are not provided with Exim. Other programs are needed in addition to Exim if you want to provide the same kinds of “group-ware” functionality as GroupWise, Exchange and Lotus Notes.