I hope you've provisioned a bit more bandwidth onto your various DNS servers that are handling your whiet/blacklists. About a 2 months ago there seemed to be some sort of confusion where you took your HIL list down, changed it's name and then changed it to zone-xfer only. Not a lot of fun for Spamasassin users which had it configured in by default (and others no doubt).
That query configuration in SpamAssassin was incorrect, and has been fixed in 2.60. While I apologize that it caused you an inconvenience, it was in fact set up like that without our knowledge. It was querying the HIL even if there were no Habeas headers present in the inbound email in question, so it was querying the HIL for every single piece of email going through SA. In fact, it was the mass querying (8000 queries per second) even with no Habeas indicator present which caused us to have to make that change. Our servers are set up properly, and are stable. Anne