Proxying in the Way of 1.4?

At the moment, proxying is the most heavily discussed issue on the developers list. The core problem is that, with 1.4, module URLs have been introduced which are located outside a publication's URL space. The question is whether proxying should be responsible of mapping these URLs into the website space, or if we should change Lenya and introduce a reserved URL space for modules within publications. Feel free to join the discussion.