It means, that, if you compare two references for a business interface of a stateless session bean, equals() always returns true (in contrast to business interfaces of stateful session beans) - see core spec 3.4.5:
// Assume
Test is a business interface of a SLSB
@EJB Test t1;
@EJB Test t2;
...
t1.equals(t2); // -> returns true
This reflects the fact that for a stateless session bean it doesn't matter which bean instance is used to process a business method invocation.