Rails urls

Nope, rails doesn't handle this. This is not a standard setup for
applications, so you'll have to write some custom code. My publishing
system Mephisto does something similar, however. Domains map to sites
(www.rubyonrails.org, weblog.rubyonrails.org, and prototypejs.org all
run on the same mongrel cluster). I use a catch-all route to handle
custom paths that renders the public content. Here's a real
simplified routes file:

# add admin routes first
map.admin 'admin', :controller => 'admin/overview', :action => 'index'

# put this at the bottom, it sends custom paths to this controller/action
map.connect '*path', :controller => 'mephisto', :action => 'dispatch'