Web Based IMAP Mail Program for Plesk based on Horde

IMP is the Internet Messaging Program, one of the Horde components.  
It provides webmail access to IMAP and POP3 accounts.
The Horde Project writes web applications in PHP and releases them under the
GNU Public License.  For more information (including help with IMP) please
visit http://www.horde.org/.

WWW: http://www.horde.org