A system with two classes is compiled, where one of the classes is
mentioned in an option clause in the Ace file.  Both classes are in
the same cluster and the Ace file uses "all" to include all classes in
the entire directory tree.  Then a new sub-directory is created and
the class is moved into that sub-directory.  When the system is
recompiled, the compiler reports a bogus VD16 error.

Discovered in release 5.3.0620.