> I'll have to check and see why kmail has that as the default. enabling
> RBL's
> doesn't have to query them everytime does it? meaning does it cache them.

No, SA doesn't cache them, and does test them every time. Running a caching
DNS server somewhere near the SA machine (possibly on the same machine) is a
good idea. It depends on your mail load. If this is a personal-use machine
the cache probably isn't needed.