/etc/imapd.conf

Here is the basic required information:

configdirectory: /var/lib/imap
partition-default: /var/spool/imap
admins: cyrus
sievedir: /var/lib/imap/sieve
sendmail: /usr/sbin/sendmail
hashimapspool: true
sasl_pwcheck_method: auxprop
sasl_auxprop_plugin: sql
sasl_mech_list: PLAIN LOGIN
sasl_sql_engine: mysql
sasl_sql_user: mail
sasl_sql_passwd: <the mysql user mail's password>
sasl_sql_hostnames: <HOSTNAME OR IP OF MYSQL MACHINE>
sasl_sql_database: mail
sasl_sql_select: SELECT password FROM accountuser WHERE username = '%u@%r' \
    OR (username ='%u' AND domain_name = '') 
virtdomains: userid
unixhierarchysep: yes
altnamespace: yes