namespaced controllers routing - params and url_for

routes.rb:

namespace :admin do
  root :to => 'index#index'
  match ":controller(/:action(/:id))"
end
root :to => "site/games#index"
namespace :site do
  root :to => redirect('/')
  match ":controller(/:action(/:id))"
end

When I type in direct URL into the browser, all works fine, like:
localhost:3000/admin/ -> admin/index#index
localhost:3000/admin/reports -> admin/reports#index
localhost:3000/site/ -> site/games#index
localhost:3000/site/security/login -> site/security#login

but when I look in the params, it's not that good:

--- !map:ActiveSupport::HashWithIndifferentAccess 
action: index
controller: reports

(controller should be admin/reports)

Now, because of that - url_for doesn't work as expected:

url_for :controller => 'admin/index', :action => 'index' WORKS FINE
url_for :controller => 'admin/reports', :action => 'index' DOESN'T WORK: No route matches {:controller=>"admin/reports"}
url_for :controller => 'site/security', :action => 'login' DOESN'T WORK: No route matches {:controller=>"site/security", :action=>"login"}

url_for :controller => 'reports', :action => 'index' DOES WORK, but it sends to admin/reports even if called in site/security/login

etc.

If I swap the namespaces declarations, it's all working fine inside "site/" but does not inside "admin/".