> But I wonder if these extensions are even required to address the current
> namespace-related issues/problems being discussed.
>
> What am I missing?

Mostly the human factors. It is true that Smalltalk already has namespaces.
It is equally true that -strictly speaking- we don't need namespaces anyway.
We have objects, everything is an object, so why bother using namespaces at
all? ;-)

So the point we're discussing here is how to introduce an old and even
existing concept in an accessible way, in a way where it will be understood
by other than hardcore Smalltalkers "in the right way". The whole point here
is that while you're right that classes already define namespaces, noone,
not a single package that I find at SM uses them in the way you're
describing. Which to me means only one thing: It isn't recognized (by
people!) as a solution that actually addresses their needs. Someone (I think
it was Dan but I might be wrong ... at least I remember the quote from him)
said "if two things are almost the same, then either make them the same or
make them very different". In this situation I'm leaning towards the latter
so that even if Smalltalk has namespaces already these "kinds of namespaces"
can be more easily recognized as addressing a particular problem.

Cheers,
  - Andreas