ActivationGroup_Stub is a stub class
for the subclasses of java.rmi.activation.ActivationGroup
that are exported as a java.rmi.server.UnicastRemoteObject.
No replacement. The setRef method
was intended for setting the remote reference of a remote
stub. This is unnecessary, since RemoteStubs can be created
and initialized with a remote reference through use of
the RemoteStub(RemoteRef) constructor.