======== Required information ====
- iRedMail version: 0.8.7
- Store mail accounts in which backend (LDAP/MySQL/PGSQL): MySQL
- Linux/BSD distribution name and version: debian 7
- Related log if you're reporting an issue:
====

    Is there any particular reason why alias is not implemented in dovecot2.conf?
    Seems to be supported in dovecot 2.1.X
   
    # Reference: http://wiki2.dovecot.org/MailboxSettings
   

   
dovecot2.conf
https://bitbucket.org/zhb/iredmail/src/ … at=default

dovecot22.conf
https://bitbucket.org/zhb/iredmail/src/ … at=default
    # This is an alias mailbox for "Sent".
    # Reference: http://wiki2.dovecot.org/MailboxSettings
    mailbox "Sent Messages" {
        auto = no
        special_use = \Sent
    }