Change mailboxes storage directory after installation

==== Required information ====
- iRedMail version: 0.8.7
- Store mail accounts in which backend (LDAP/MySQL/PGSQL): LDAP
- Linux/BSD distribution name and version: Ubuntu 12.04
- Related log if you're reporting an issue:
====

Hi. So I set up a mail server using iRedMail. As it was being installed, we used the default directory for the storage of the mailboxes which was /var/vmail

Now that our mail server is up and running, I was asked if it's possible to change the default directory for the mailboxes (perhaps a new folder instead of /var/vmail). If so, how can I do it?

Thank you so much.