You should setup everything as if Avast! is not installed (according to Spamihilator help files)

  1. make yourself sure, that spamihilator is really running on port 120 (Settings / Connection in Spamihilator)

  2. in Outlook Express account
    server: 127.0.0.1
    port: 120
    username: mail.anyserver.com&anyuser

  3. For the “POP3 notifier” use:
    username: username
    server: mail.anyserver.com
    port: 110