I finally gave up on weblogic 6.1, and scrapped it. I could never find anything on their site, their support was inadequate for the amount of money we paid for that thing, and I personally found bea dragging their feet when it came to keeping up with the new vm's, and standards. You might look for a new server. It would be much less trouble in my own personaly opinion/experience.
You're right about BEA support, it always has been terrible. It's the insistence of going through three layers of freshmen before you finally get to someone that understands your problem, and by this time, you've probably got so fed up waiting you've either solved it or found a workaround.
As for standards though, you're wrong on that one. BEA are always miles ahead of anyone else on standards. Specifically they were about a year ahead of WebSphere with EJB 2.0 support.
I suggest you have a look at their site again for the service pack, they are there somewhere.
As for VM, BEA bought out JRockit, I don't think you'll find a newer VM than that at the moment.
8.1 supports min JDK 1.4 so it;s hard to see how much more up to date they could be.
I've used WLS successfully on several greenfield projects and would be my app server of choice.
Providing the runtime licenses don't price us out of the market