Exim Authentication with Dovecot – Configuring Exim Authentication Using Dovecot Driver

Been following the instructions at the Dovecot Wiki for setting up Exim to share authentication credentials with Dovecot. I have setup Dovecot to deliver mails for virtual users and setup a router and transport within exim to deliver to these v-user's Maildirs. I cannot seem to get the configuration detailed below to work in order to use the same user creds for SMTP auth.

http://wiki.dovecot.org/HowTo/EximAndDovecotSASL

Exim configuration error in line 841
of
/var/lib/exim4/config.autogenerated.tmp:
authenticator dovecot_login: cannot
find authenticator driver "dovecot"

I receive this error every time I try and reload my configuration.

According to the exim docs, support for this driver has been included since version 4.64, and I am currently using 4.71. I'm not sure why the configuration for this authenticator would not work.

dovecot_login:
  driver = dovecot
  public_name = LOGIN
  server_socket = /var/run/dovecot/auth-client
  server_set_id = $auth1

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

Dovecot also has a socket setup for auth.

  socket listen {
    client {
      path = /var/run/dovecot/auth-client
      mode = 0666
    }   master {
      path = /var/run/dovecot/auth-master
      mode = 0600
    } }

I'm uncertain why the MTA is unable to use this configuration, especially since this driver is supposedly a default. Would appreciate any help from Exim vets – I'm a python developer filling in for our sysadmin so I'm at a bit of a loss. Server is Ubuntu 10.04.