@DataModelSelection in stateful bean

[kaviarasu]

Code:
@Stateful
@Scope(SESSION)
@Name("usermessage2")
public class UserComments implements Serializable, UserDisplay1 {
 private static final long serialVersionUID = 1L;
 @DataModel
 private List userList2;

 @DataModelSelection
 @Out(required=false)
private TblComments1 message;

 @PersistenceContext
 private EntityManager em;
 long productid=1001;
 @Factory("userList2")

im using the above code
but it giving me error Could not create Component: usermessage2
can any one give me suggestion