I recently added dbl.spamhaus.org to my system and see that they do not permit lookups by IP address.  From my quarantine table I can see that spamfilter must be attempting resolution by IP address if found in the message body.

It would be nice to use spamhaus new domain blacklist, is there some way to define the SURBL but tell it not to send lookups for IP addresses?

If you do lookup an IP address it returns a positive match with an error not do to IP queries, that causes messages to be quarantined in error.