filter-dnsbl and Abusix

[J Doe]

Hello,

I have configured OpenSMTPD to make use of: filter-dnsbl:

    /etc/mail/smtpd.conf
        . . .
    filter check_abusix proc-exec "filter-dnsbl -v
        <key>.black.mail.abusix.zone" user _dnsbl group _dnsbl
        . . .
    filter port_25_filters  chain { check_rev_DNS, check_spamhaus,
check_abusix... }

...however, if I try either the combined DNSBL from Abusix or the black
DNSBL from Abusix, it will reject mail from Hotmail as well as e-mail
that is hosted via 1&1's e-mail service.

The man page for filter-dnsbl mentions Abusix, so I am assuming it
supports it, but why would this be happening ?  It seems like all
responses via Abusix are detected as spam.

Does anyone else make use of Abusix and see this behaviour ?

Thanks,

- J