Unsubscribe from shared mailbox

Hi,

I'm using Dovecot 2.2.13-11 (Debian Jessie) and shared namespace (to be old Cyrus compatible setting):

namespace { list = children location = maildir:/vmail/user/%%n/Maildir:INDEXPVT=/vmail/user/%n/Maildir/Shared/%%n prefix = user.%%n. separator = . subscriptions = yes type = shared }

My account: milo Other account: peter

After subscription, I have: /vmail/user/milo/Maildir/Shared/peter/.INBOX/dovecot.index.pvt.log

After unsubscribe, file and folder still exists. Where Dovecot stores the information, that I had unsubscribed from this folder? I need this to analyze subscriptions over all mail acounts.

Thank you, Miloslav