The rmic stub compiler doesn't generate correct code in the case where
one remote implementation extends another remote implementation.
The remote methods from the extended class do not appear in the stub.

The program below show this problem. It assumes the javaTest harness
is available and that stubs have been generated by running rmic, i.e.

% javac -d . ImplExtendsImpl.java
% rmic -d . tests.api.java.rmi.rmic.Bimpl
% java tests.api.java.rmi.rmic.ImplExtendsImpl