Dallas (and all the rest), what you're saying is: - We're talking of forward lookups, not of reverse lookup.
What I'm seeing, however, is that the zone files contain IPs in reverse notation.So SA does a forward lookup on a reversed IP. I think that's about it. Wolfgang complained about not being able to resolve 219.144.194.158.multi.surbl.org, and that's true. The zone files contain an entry for 158.194.144.219.multi.surbl.org, which - to me at least - is wrong as SA is douing forward lookups on it.
Dirk