CORBA35 — DynValue & custom valuetypes

The CORBA 2.3.1 specification does not cover the interaction between the
DynValue interface and custom valuetypes.

I frankly don't see any way that the DynValue interface can possibly
correctly handle a custom valuetype when the ORB does not have a factory
for the type. It is theoretically possible for DynValue to properly
work with a known custom type, but the implementation strategy could not
be based on parsing the marshalled form of the valuetype.

So, there are two issues that need to be addressed:

1. Should DynValue handle custom valuetypes at all?

2. For the set of custom valuetypes that it cannot handle, what
exceptions should be raised by each operations?