[Exim] Problem using LOGIN authentification

Dear Exim users,

I'm running Exim 3.33, which works rather fine. The only problem I
have is with users running Outlook Express, any version. They canot
authenticate to Exim, while they could to the former server, who was
running Postfix.

This is what I set up in Exim, and MD5 auth works, whereas LOGIN
doesnt.

fixed_plain:
  driver = plaintext
  public_name = PLAIN
  server_condition = \
    ${if and {{eq{$2}{gci}}{eq{$3}{xxxxxx}}}{yes}{no}}
  server_set_id = $2

fixed_login:
  driver = plaintext
  public_name = LOGIN
  server_prompts = "User Name : Password"
  server_condition = "\
    ${if and {{eq{$1}{gci}}{eq{$2}{xxxxxx}}}{yes}{no}}"
  server_set_id = $1

This is what exim logs:

2001-10-22 16:06:28 Authentication failed for mailback.its-toasted.org
(ck) [213.68.72.69]: 535 Incorrect authentication data

This is what the users computer logs:

Ein unbekannter Fehler ist aufgetreten. Konto: 'gci-management.com',
Server: 'mailback.its-toasted.org', Protokoll: SMTP, Serverantwort: '334
VXNlciBOYW1l', Anschluss: 25, Secure(SSL): Nein, Serverfehler: 334,
Fehlernummer: 0x80004005

Outlook (here v5.0) gets a server reply of 334, whereas it expected
250 or 5xx. I guess I did something wrong with the auth driver, but
I'm not sure. I copied them from the webpage.

Thank you for any input!

Cheers,
 Johannes                            mailto:jmp@its-toasted.org
-- 
I haven't lost my mind; I know exactly where I left it.