1. install dovecot

   sudo apt-get install dovecot-imapd dovecot-pop3d


2. change (sudo nano /etc/dovecot/dovecot-postfix.conf)
   Note: /etc/dovecot/dovecot.conf wouldn't work. 

   disable_plaintext_auth = no


3. sudo /etc/init.d/dovecot restart


4. test

   telnet smtp.icc-computer.com pop3

   or:

   telnet smtp.icc-computer.com imap2