If you, like me, like to try out Glassfish v3 with its build in support for JavaEE6 and JSF 2, don’t even try to use the Glassfish v3 Preview Edition available on the Glassfish website.
Instead, use one of the nightly builds
http://download.java.net/glassfish/v3/nightly/
You will save yourself a lot of headaches.