ClassCastException casting to same class when EntityManager is shared between two isolated applications in JBoss EAP?

Issue

• We have two applications running on EAP. Both applications are packaged as EARs. We are getting this exception:

Caused by: java.lang.ClassCastException: com.jboss.examples.jpa.ExampleEntity cannot be cast to com.jboss.examples.jpa.ExampleEntity

We think this is a Class Loader isolation problem. The class com.jboss.examples.jpa.ExampleEntity is contained in a common JAR along with a persistence.xml that is packaged in both EARs. We have isolation enable on both EARs. The common JAR has a persistence.xml which is specifying the JNDI name for the EntityManagerFactory as such:

<persistence xmlns="http://java.sun.com/xml/ns/persistence"
   xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
   xsi:schemaLocation="http://java.sun.com/xml/ns/persistence http://java.sun.com/xml/ns/persistence/persistence_1_0.xsd"
   version="1.0">

  <persistence-unit name="example-jpa.jar" transaction-type="RESOURCE_LOCAL">
    ...
    <properties>
         ...
         <property name="jboss.entity.manager.factory.jndi.name" value="java:/ExampleEntityManagerFactory"/>

    </properties>
  </persistence-unit>
</persistence>