Routes in Ruby on Rails are case sensitive. It seems someone brought this up before, and it has been labeled will not fix.
http://rails.lighthouseapp.com/projects/89
I've just has the same problem, and solved it using middleware - have a look here:
http://gehling.dk/2010/02/how-to-make-rails-routing-case-insensitive/
Note: This only applies for Rails 2.3+