OneLDAP is a limited LDAP server that is a proxy to other common protocols, such as POP3 and IMAP. It provides basic SEARCH and BIND functions for standard LDAP authentication. It is based on the shell backend function of OpenLDAP. Release files are available at the project website.
This is an email server in a box. Using ldap authentication for imap, pop3, smtp, and SSL/TLS versions of each. Includes web user-interface, web administration, web filters. Installs on top of RedHat in under 20 minutes by running one script.