[Dovecot] How to lock a user out?

Hi,

We are considering to migrate to Dovecot. We can running uw-imap and have a local path which allow us to lock a user by creating a .lockdir directory in the user home directory and put our warning message to .lockdir/mbox. The locked user can still receive messages in ~/mbox. But can not access any messages except ~/.lockdir/mbox. I wonder if Dovecot has any similar feature which we can use to lock a user out without affecting the mail delivery?

Kai Wang University of Calgary