Using the ruby debugger in tests

Is there any way to attach the ruby debugger to a functional test? I was hoping that something like : ruby -r debug test/functional/hot_seat_controller_test.rb would work, but it dies with the following trace:

./script/../config/boot.rb:14: `uninitialized constant Rails' (NameError)          from /usr/local/lib/ruby/site_ruby/1.8/rubygems/custom_require.rb:21:in `require'          from script/runner:3 ./script/../config/boot.rb:14:unless defined?(Rails::Initializer)

Any ideas? Jon

$ gem install ruby-debug $ rdebug test/functional/hot_seat

_controller_test.rb