[Dovecot] Denying user won't work as expected

[Frank Bonnet]

Hello
I tried to use the "deny user" feature but it does not work as expected ...
( dovecot 2.0.12 ) we use LDAP as authentication source

I modified the 10-auth.conf file as the following

# <doc/wiki/UserDatabase.txt>

!include auth-deny.conf.ext
#!include auth-master.conf.ext

#!include auth-system.conf.ext
#!include auth-sql.conf.ext
!include auth-ldap.conf.ext
#!include auth-passwdfile.conf.ext
#!include auth-checkpassword.conf.ext
#!include auth-vpopmail.conf.ext
#!include auth-static.conf.ext

I modified the auth-deny.conf.ext file as the following

passdb {
  driver = ldap
  deny = yes

  # File contains a list of usernames, one per line
  args = /usr/local/etc/dovecot/deny-users
}

I have tested writting one user (me) in the 
/usr/local/etc/dovecot/deny-users
and the result is the login is denied for ALL users ...

If I do not uncomment the
!include auth-deny.conf.ext

line in 10-auth.conf file everything works well
I really need this feature

Thanks for any help