Rails 2.1 and map.root

I moved my project from rails 2.0 to 2.1 and map.root stop working: It means if I have e.g:     map.root :controller => 'sessions', :action => 'new' it not working, but when I try do this    map.new_session :controller => 'sessions', :action => 'new'    map.root :new_session I have error: /usr/lib/ruby/gems/1.8/gems/actionpack-2.1.0/lib/action_controller/routing/builder.rb:197:in `build': Illegal route: the :controller must be specified! (ArgumentError)

any ideas?

Sorry:

it works: map.root :controller => 'sessions', :action => 'new'

but this:

map.new_session :controller => 'sessions', :action => 'new' map.root :new_session

not working, but in rails 2.1 it should....

any ideas?