paypal-2.0.0 HELP!!

ok I installed the gem but it doesn't work...

get get:

NameError in PaypalController#index uninitialized constant PaypalController::Paypal RAILS_ROOT: /home/steven/nwdentaltemps

Application Trace | Framework Trace | Full Trace /usr/lib/ruby/gems/1.8/gems/activesupport-2.0.2/lib/active_support/ dependencies.rb:478:in `const_missing' app/controllers/paypal_controller.rb:12:in `index' /usr/bin/mongrel_rails:19:in `load' /usr/bin/mongrel_rails:19

is it my install of ruby, am i doing something wrong? or is this plugin out of date..