The following are the requirements for the session bean’s business interface:
1.The interface must not extend the javax.ejb.EJBObject or javax.ejb.EJBLocalObject interface.
4.The bean class must implement the interface or the interface must be designated as a local or
remote business interface of the bean by means of the Local or Remote annotation or in the
The above text says that Session Bean Remote Interface must extend the javax.ejb.EJBObject interface.
Suppose there is business interface Advise.Then(as per section 4.9.7),it must not extend the javax.ejb.EJBObject and should be designated as either Local or Remote.
Lets say that Advise is designated as Remote via DD.Then,(as per section 4.9.9)a Session Bean Remote Interface must extend javax.ejb.EJBObject interface.