During the region conversion process for the Havok4 Early Adopter Program, a problem was found that required us to convert existing regions back to Havok1 temporarily. I expect that this issue will be resolved in short order, and hope to have a new version of the Havok4 simulator ready to deploy during this week. We will be re-deploying the Havok4 simulator to all regions on the request list as soon as an updated version has passed testing.
I want to take a minute to say a big thank you to all of our dedicated beta testers and early adopter users for your support, and for your help with identifying and resolving issues. Your work is making a big difference in helping to make Second Life better for everyone.
If you have not signed up to be a part of the Early Adopter Program, please see this post http://blog.secondlife.com/2008/01/18/announcing-the-havok4-early-adopter-program/ for more details.
Havok4 Program Manager