I have been deploying a EAR on JBoss 4.2 using the JEE5 application.xml directive "library-directory" so that my shared libraries are made available to all my ejbs, sars, and wars within the application. Worked great.
Tried to move to JBoss 5, and deploy the exact same ear, but I get ClassNotFound exceptions all over the place. I did notice that the EARDeployer was modified slightly, but was wondering if anyone else has seen this issue or has had similar problems? I did not see a bug report for it, though.
If you look at the release dates, 5.0 beta 2 came out in April while 4.2.1 came out in July. A lot of changes in EJB3 went into 4.2.1 that do not appear in 5.0 beta 2 (and if I recall correctly, this was one of them). According to the rumors I have heard, 5.0 beta 3 should be out around the end of this month, wait until then before using it.