We are a bit tight on SMP servers at the moment, as we are waiting for a new big server to come back on line. Our admins have been working on this problem and think they have found the issue with the raid on that machine (after consulting the hardware manufacturer, they're upgrading the firmware of the drives). We don't have an ETA on this, but I'm hoping it will be relatively soon.
After the new machine comes on line, we should have a lot more SMP power. Moreover, we have other servers waiting in the wings and our plan is to bring several servers on line for SMP in the coming weeks with new WUs and SMP projects (although note that it takes a while for new projects to go through our QA process).
All of this is in anticipation of the v7 client maturing and going into open beta in a few months. V7 should make it a lot easier to run SMP. However, it's also important to note that the v6.30 client (already released and on our high performance client download page) already makes SMP pretty easy to run.