I was having the same kind of problem, see http://www.jboss.org/index.html?module=bb&op=viewtopic&p=4219306. To resolve these classloading issues you have to ensure that the classloader that hibernate uses knows about (i.e. can load) your hbm.xml files and the entity classes. For now I resolved the classloading issues by placing these files under deploy/jbpm/jbpm-enterprise.jar/. Of course this is just a hack. A better solution should be packing everything into a single EAR. It might be possible to change the classloading to enable hibernate getting access to the par file's content. The Eclipse OSGI implementation has "Buddy Policy" to resolve similar issues (see http://wiki.eclipse.org/index.php/Context_Class_Loader_Enhancements). This would be the best solution (since then the entities could be versioned too) but I think that it would require changes to the jBPM sources. Volker View the original post : http://www.jboss.org/index.html?module=bb&op=viewtopic&p=4222605#... Reply to the post : http://www.jboss.org/index.html?module=bb&op=posting&mode=reply&a...