[Dovecot] Thinking about switching from courier-imap to Dovecot: 2 simple questions

Hi, I'm using RHEL4 and since the dovecot RPM is present in the main repository, I'm thinking about switching from courier-imap (with whom I've got trouble to update) to Dovecot. Here are two questions about Dovecot (google didn't answer me):

1. Is it possible for dovecot to use the bind mecanism against ldap for authentification purpose. My main concern is to avoid the clear-text password in the dovecot-ldap.conf file. With courier-imap, the process simply bind to the ldap tree with the users's supplied login/password. No need for a special authentification purpose user.

2. Does imap's dovecot implementation support folders imbrication (more than one level folders) ?

Thanks, kfx.