[Dovecot] Exim Dovecot Authentication Problem

[Marc Perkel]

Having a hard time figuring out something that is supposed to be easy. 
Tryiong to configure Dovecot so that it provides authentication to Exim 
for outgoing smtp. Tried different things and getting

authentication socket protocol error

dovecot_plain:
  driver = dovecot
  public_name = PLAIN
  server_socket = /var/run/dovecot/auth-client
  server_set_id = $auth1

auth default {
  # Space separated list of wanted authentication mechanisms:
  #   plain digest-md5 cram-md5 apop anonymous
  mechanisms = plain
 
  #
  # Password database is used to verify user's password (and nothing more).
  # You can have multiple passdbs and userdbs. This is useful if you want to
  # allow both system users (/etc/passwd) and virtual users to login without
  # duplicating the system users into virtual database.
  #
  # http://wiki.dovecot.org/Authentication
  #

  # PAM authentication. Preferred nowadays by most systems.
  # Note that PAM can only be used to verify if user's password is correct,
  # so it can't be used as userdb. If you don't want to use a separate user
  # database (passwd usually), you can use static userdb.

  passdb passwd-file {
    # Master users that can log in as anyone
    args = /etc/dovecot.masterusers
    master = yes
    pass =yes
  }


  # Linuxconf passwd-like file with specified location
  passdb passwd-file {
    args = /etc/exim/control/vmail/shadow.%d
  }


  # Linuxconf passwd-like file with specified location
  userdb passwd-file {
    args = /etc/exim/control/vmail/passwd.%d
  }

  # User to use for the process. This user needs access to only user and
  # password databases, nothing else. Only shadow and pam authentication
  # requires roots, so use something else if possible. Note that passwd
  # authentication with BSDs internally accesses shadow files, which also
  # requires roots. Note that this user is NOT used to access mails.
  # That user is specified by userdb above.
  user = root


  # Number of authentication processes to create
  count = 10

}


# It's possible to export the authentication interface to other programs,
# for example SMTP server which supports talking to Dovecot. Client socket
# handles the actual authentication - you give it a username and password
# and it returns OK or failure. So it's pretty safe to allow anyone 
access to
# it. Master socket is used to a) query if given client was successfully
# authenticated, b) userdb lookups.

# listener sockets will be created by Dovecot's master process using the
# settings given inside the auth section

auth default_with_listener {
  mechanisms = plain

  passdb passwd-file {
    # Master users that can log in as anyone
    args = /etc/dovecot.masterusers
    master = yes
    pass =yes
  }

  passdb passwd-file {
    # Path for passwd-file
    args = /etc/exim/control/vmail/shadow.%d
  }

  userdb passwd-file {
    # Path for passwd-file
    args = /etc/exim/control/vmail/passwd.%d
  }

  socket listen {
    master {
      path = /var/run/dovecot/auth-master
      mode = 0666
    }
  }
}

auth external {
  mechanisms = plain

  passdb passwd-file {
    # Master users that can log in as anyone
    args = /etc/dovecot.masterusers
    master = yes
    pass =yes
  }

  passdb passwd-file {
    # Path for passwd-file
    args = /etc/exim/control/vmail/shadow.%d
  }

  userdb passwd-file {
    # Path for passwd-file
    args = /etc/exim/control/vmail/passwd.%d
  }

  socket listen {
    client {
      path = /var/run/dovecot/auth-client
      mode = 0666
    }
  }

}