Seam Injection on EJB fails IllegalArgumentException: object is not an instance of declaring class in JBoss EAP

Issue

• Our application is a JEE 5 application using Seam which fails to inject on EJB components. They are found using JNDI without any issues, but injection of entitymanagers or other components fails. The error below is in the log:

...
Caused by: java.lang.IllegalArgumentException: Could not invoke method by reflection: PrintJobDaoImpl.setEntityManager(javax.persistence.EntityManager) with parameters: (org.jboss.seam.persistence.EntityManagerProxy) on: com.jboss.examples.jpa.ExampleDaoImpl
  at org.jboss.seam.util.Reflections.invoke(Reflections.java:32)
  at org.jboss.seam.Component.setPropertyValue(Component.java:1914)
  ... 158 more
Caused by: java.lang.IllegalArgumentException: object is not an instance of declaring class
  at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
  at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
  at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
  at java.lang.reflect.Method.invoke(Method.java:597)
  at org.jboss.seam.util.Reflections.invoke(Reflections.java:22)
  ... 159 more