dovecot - Jan 2014 - A variable for the unix user or home path would be useful in some cases

Hello,

In our hosting environment, we let users share mailboxes across all
their domains and think it's best if the shared mailbox listing (in a
file) stays in their unix home path. That would be:
/home/USER/imap/shared-mailboxes.db

Unfortunately, it seems there is no way to generate that path using a
variable. Something like this would be convenient:
acl_shared_dict = file:%v/imap/shared-mailboxes.db

Instead, we have to use something like this:
acl_shared_dict = file:~/../../../shared-mailboxes.db
which only works for virtual users.

Did somebody solve this another way?

Could we have the unix user or home path as a variable?
Or could we have a modifier giving us the path or the unix user based on
the unix UID?

Cheers,

Olivier