mysql_virtual_alias_maps.cf

user = mta
password = password
hosts = localhost
dbname = sys_mta
table = alias
select_field = goto
where_field = address

mysql_virtual_domains_maps.cf

user = mta
password = pass
hosts = localhost
dbname = sys_mta
table = domain
select_field = domain
where_field = domain
additional_conditions = and active = '1'

mysql_virtual_mailbox_limit_maps.cf

user = mta
password = pass
hosts = localhost
dbname = sys_mta
table = mailbox
select_field = quota
where_field = username
additional_conditions = and active = '1'

mysql_virtual_mailbox_maps.cf

user = mta
password = pass
hosts = localhost
dbname = sys_mta
table = mailbox
select_field = maildir
where_field = username
#additional_conditions = and active = '1'