Non numeric IDs in member resources

I have a nested resource:

map.resources :posts do |posts|
   posts.resources :comments
end

which generates urls like:

posts/1/comments/2

Is there any way to use a "name" or other parameter instead of
params[:id] for posts?. In other words I'd like to have a url like

posts/some-name-here/comments/2

Is something like resource_hacks my only hope?

http://archive.jvoorhis.com/articles/2006/08/01/announcing-resource_hacks

-vega