By any chance, did you get this figured out? I am having the same problem...please let me know.
Hi, I cannot say that I found the problem exactly. I think this is caused by some invalid packaging. I was using maven for building package, and it was adding some jar's in the war. I guess one of the libraries were causing the exception.
I'm using ant for building and packaging. ant script doesn't include any libraries in the war and I don't have the exception again.
Hope this helps.