Store ACL files within shared mailbox / rename shared folder problem

Hi.

If $otheruser shares a mailbox to $myuser, my private index is stored in *my* Maildir, according to this template (from the dovecot docs):

mail_location = maildir:%%h/Maildir:INDEXPVT=%h/Maildir/shared/%%u

If $otheruser renames the shared mailbox, all my private mail flags (Seen) are lost because my mailclient couldn't find the private index anymore.

Is there any way to store the private index within the shared mailbox? If $otheruser renames the mailbox, the index will be 'migrated' as well. Something like this:

/data/mails/$otheruser/Maildir/.MagicSharedFolder/shared/$myuser.dovecot.index.pvt.log

I see no way on how to do craft a INDEXPVT for this.

Kind regards, Chris