> how hard will it be to work out a script, that update the namespace automatically? it would even be possible to do that in the bytecode level I think.

Java has reflection, so classes can be loaded by name at runtime (and the name might have come from a XML file somewhere, or be the result of string concatenation); also, the name of a class can be easily obtained so code can depend on that (for instance, a logging configuration XML file). That's before considering that some libraries generate classes on the fly (by dynamically generating and loading bytecode, which include class names).