Courier Description
Courier's mail transfer agent (MTA), an integrated mail/groupware service, is based on commodity open protocols such as ESMTP and IMAP. It also supports SSL, LDAP and HTTP. Courier offers ESMTP, IMAP and POP3 services, webmail and mailing lists within a single, consistent framework. Individual components can easily be enabled or disabled. The Courier mail module now integrates basic web-based scheduling and calendaring services into the webmail module. Soon, advanced groupware calendaring will be available.
The Courier mailserver's source code should be able to compile on all POSIX-based kernels, including Linux and BSD. The Courier mailserver should also compile under Solaris and AIX with the help of Sun's or IBM’s freeware addon tools for each operating system.
The Courier mailserver evolved from several related projects that were merged together (more about that later). The Courier mailserver implements SMTP extension for mailing list management.