[Dovecot] LDAP encryption

We have an LDAP server that contains AES encrypted passwords. So far I've been able to use this by adding a passdb module that encrypts the user's password prior to ldap comparison. Now I am looking at supporting client-side encrypted passwords. To do this I need to decrypt the password returned by LDAP. Is there a way to insert a module to do this decryption between ldap returning and the auth mechanism?