I ran into this problem too. I was unable to get the plain treecache to work with 1.4.2_10, though it is supposed to be supported in jbosscache 1.4.
After days of banging my head, I installed jdk 1.5.0_08 and it worked. Maybe there was something else wrong but I couldn't find it. Hopefully this is the reason for the success and that it might help someone else in the same boat.
Check your classpath. What does MBeanServerFactory list?
even iam encountering the same problem .....
what is the mistake iam doing. iam running my jboss portal server 2.6.3 GA.
I am stuck with the same problem. Can anybody pls throw some light on this issue?