Creation of a related EJB2 entity fail with error

Issue

• If business code inside the entity is invoked during creation the code fail
• "JBAS014171: Instance for PK [....] already registered" during entity creation after the ejbCreate method was invoked
• After migration from EAP4 or EAP5 to EAP6 the entity could not created and throw and Exception with the error code "JBAS014171"

A code Example

class ParentBMPEntityBean {
  public ParentBMPPK ejbCreateWithChildSamePK(String code, long id, String name) throws CreateException {
    ParentBMPPK pk = new ParentBMPPK(code, id);

    setCode(code);
    setId(id);
    setName(name);

    try {
      ChildBMPEntityLocalHome childHome = (ChildBMPEntityLocalHome) new InitialContext().lookup("java:app/EJB2examples-bmp-one2one-ejb/ChildBMPEntity!de.wfink.ejb2.examples.bmp.ChildBMPEntityLocalHome");
      childHome.create(this.code, this.id, this.id, "ChildBMP for "+this.name);
    } catch (NamingException e) {
      new RuntimeException("Could not lookup ChildBMPEntityLocalHome",e);
    }

    return (pk);
  }

  public void ejbPostCreateWithChildSamePK(String code, long id, String name) {}
}

class ChildBMPEntityBean {
  public ChildBMPEntityPK ejbCreate(String code, Long id, Long parentId, String name) {
    ...
    // check that the parent exists
    try {
      setParent(parentLocalHome.findById(parentId));
    }catch(Exception e) {
      throw new RuntimeException("Parent does not exists");
    }
  }
}