I solved the problem now. The solution is to use EAR and package the jboss-seam.jar library in the EAR instead of deploying JAR and WAR without an EAR and having jboss-seam.jar twice. The actual implementation of Seam does NOT support the separation of Web container and EJB container. When using Seam, they must be collocated and the deployment must be done with EAR. The J2EE spec allows you to deploy EJB and Web artefacts independently but Seam deployment restricts you to EAR deployment only, and moreover forces the EJB and Web part to share the Seam library in a common class loader. I hope this is only an implementation issue and not conceptual. I didn't found any note on that. Unfortunately. This restriction has severe consequences, not only on packaging for a single application server but naturally also on different app servers: Seam does NOT support remote EJB. I didn't found any note on that too. Perhaps I missed some documentation... Bottom line: YOU HAVE TO PUT THE JBOSS-SEAM.JAR IN THE EAR FILE AND NOT IN THE JAR AND WAR FILES. Cheers Alain Hsiung View the original post : http://www.jboss.com/index.html?module=bb&op=viewtopic&p=4044688#... Reply to the post : http://www.jboss.com/index.html?module=bb&op=posting&mode=reply&a...