[Dovecot] Problems with apple'mail client

[Osvaldo Alvarez Pozo]

hi all
I use dovecot for smtp authentication  this works ok for thunderbird
and for outlook express but not for apple'mail client.

my config is as follow

postfx main.cf

.
.
#authentication
smtpd_sasl_auth_enable          = yes
#smtpd_sasl_local_domain        = $myhostname
smtpd_sasl_exceptions_networks  = $mynetworks
smtpd_sasl_security_options     = noanonymous
broken_sasl_auth_clients        = yes
smtpd_sasl_type = dovecot
smtpd_sasl_path = private/auth
# TLS parameters
.
.
Dovecot dovecot.conf

ssl_cert_file = /etc/ssl/certs/ssl-cert-snakeoil.pem
ssl_key_file = /etc/ssl/private/ssl-cert-snakeoil.key
mail_location = maildir:/var/vmail/%d/%u/Maildir
mail_extra_groups = mail
first_valid_uid = 5000
last_valid_uid = 5000
maildir_copy_with_hardlinks = yes
disable_plaintext_auth = no
mail_debug = no
dotlock_use_excl=yes
protocols = imap pop3
protocol imap {
  mail_plugins = quota imap_quota
  imap_client_workarounds = outlook-idle delay-newmail
}
protocol pop3 {
  mail_plugins = quota
  pop3_client_workarounds = outlook-no-nuls oe-ns-eoh
  pop3_uidl_format = %08Xu%08Xv
}
protocol lda {
  postmaster_address = support at oc3.fr
  mail_plugins = quota
  log_path = /var/log/dovecot-deliver.log
  info_log_path = /var/log/dovecot-deliver.log
}
auth default {
mechanisms = plain login
  passdb sql {
    args = /usr/dovecot/etc/sql.conf
  }
# userdb prefetch {
#  }
  userdb sql {
    args = /usr/dovecot/etc/sql.conf
  }
    user = nobody
  socket listen {
    master {
      path = /usr/dovecot/var/run/dovecot/auth-master
      mode = 0660
      user = vmail
      group = mail
    }
    client {
      path = /var/spool/postfix/private/auth
      mode = 0660
      user = postfix
      group = mail
    }
  }
}
dict {
}
plugin {
}

Thanks