Additional params arguments through routes.rb

I have a controller that I'd like to exist under two different URIs --
call it a tags controller, mapped to /tags and /my_profile/tags ...
the second URI is connected as a singleton resource. The only
difference between the two is the starting place for the find calls; /
tags finds all tags in the system, /my_profile/tags just finds _my_
tags.

Because the nesting is under a singleton resource, there's no
additional param ID to key off of, so I'd have to provide one of my
own.

In the old days of map.connect, it was trivial to add an additional
item to the params hash:

map.connect '/my_profile/tags', :controller => 'tags', :action =>
'index', :current_user => true
map.connect '/tags', :controller => 'tags', :action =>
'index', :current_user => false

I can't for the life of me find a way to pass that extra parameter in
using map.resources anymore. Am I missing something?