[exim] Spamhaus Blacklist

Hello,
Iuse the spamhaus blacklist for exim (CHECK_RCPT_IP_DNSBLS).

First of all what are the differences between CHECK_RCPT_IP_DNSBLS and
CHECK_RCPT_DOMAIN_DNSBLS ??

Make it sense to use both? if yes can I also use zen.spamhaus.org for this?

Is there also a way to report spam servers to spamhaus?
Actually I get some spam from "84.19.164.45"but this ip is not blocked
at the moment.

Regards,
Basti