I've quite a few hours trying to migrate an existing websphere app to Jboss4.0.3. I've made exactly no progress.
The structure of the ear, for better or for worse, is this:
(root.ear) - warfile - ejb jar, which also includes common code - several dozen common jars
The problem comes when Tomcat tries to load a servlet from the warfile. NoClassDefFound errors abound! It cannot find common classes from the ejb jar or any other common jar. I've tried munging with the tomcat classloading settings Java2ClassLoadingCompliance and UseJBossWebLoader to no avail. I've also tried adding the jars into the application.xml (they are not present in the websphere app).
Restructuring the app is out of the question; the idea is for me to be able to run the app in jboss for local machine development purposes, but then do serious integration testing and deployment in websphere, our corporate standard. I can rewrite config files with impunity, however. Anybody have any ideas?
(Yes, I've read several articles about this, but they go into much greater detail about sharing definitions between applications, etc; I only care about this one ear.)