Routing Error with RJS

I really need some help using RJS.

http://ip:3000/thoughts/log.rjs or
http://ip:3000/thoughts/log.js

give me a No route matches "/thoughts/log.rjs" with {:method=>get}

log.rjs and log.js are both in the thoughts view

routes.rb is

map.connect ':controller/:action/:id'
map.connect ':controller/:action/:id.:format'

Anyone?

Do I need to create a mime type for .rjs ?

is thoughts a controller?