[exim] Unblocking blacklisted email

Hi,

I found that may be apache.org is in blacklist.
How can I unblock it in my mail server?
Here is the log from mainlog:
2004-10-26 08:37:58 1CMFLU-0008rc-Pi ** list-subscribe@???
R=dnslookup T=remote_smtp: SMTP error from remote mailer after RCPT
TO:<list-subscribe@???>: host mail.apache.org [209.237.227.199]:
550 http://dsbl.org/listing?201.187.6.17
or may be 201.187.6.17 is in blacklisted?

Thanks
Sam