ArgumentError with Acts as Authenticated

I posted a previous error that I thought was attributed to attachment fu but after ripping all the attachment fu code out I'm running into similar error with acts as authenticated when I try to post several files consecutively to a server regardless of whether I do anything with them or not. Here's the error I get

ArgumentError (A copy of AuthenticatedSystem has been removed from the module tree but is still active!):     C:/ruby/lib/ruby/gems/1.8/gems/activesupport-1.4.1/lib/ active_support/dependencies.rb:237:in `load_missing_constant'     C:/ruby/lib/ruby/gems/1.8/gems/activesupport-1.4.1/lib/ active_support/dependencies.rb:452:in `const_missing'     /lib/authenticated_system.rb:11:in `current_user'     /lib/authenticated_system.rb:6:in `logged_in?'     /lib/authenticated_system.rb:53:in `login_required'     C:/ruby/lib/ruby/gems/1.8/gems/actionpack-1.13.2/lib/ action_controller/filters.rb:456:in `call'     C:/ruby/lib/ruby/gems/1.8/gems/actionpack-1.13.2/lib/ action_controller/filters.rb:435:in `call'     C:/ruby/lib/ruby/gems/1.8/gems/actionpack-1.13.2/lib/ action_controller/filters.rb:637:in `call_filter'     C:/ruby/lib/ruby/gems/1.8/gems/actionpack-1.13.2/lib/ action_controller/filters.rb:619:in `perform_action_without_benchmark'     C:/ruby/lib/ruby/gems/1.8/gems/actionpack-1.13.2/lib/ action_controller/benchmarking.rb:66:in `perform_action_without_rescue'     C:/ruby/lib/ruby/1.8/benchmark.rb:293:in `measure'     C:/ruby/lib/ruby/gems/1.8/gems/actionpack-1.13.2/lib/ action_controller/benchmarking.rb:66:in `perform_action_without_rescue'     C:/ruby/lib/ruby/gems/1.8/gems/actionpack-1.13.2/lib/ action_controller/rescue.rb:83:in `perform_action'     C:/ruby/lib/ruby/gems/1.8/gems/actionpack-1.13.2/lib/ action_controller/base.rb:430:in `process_without_filters'     C:/ruby/lib/ruby/gems/1.8/gems/actionpack-1.13.2/lib/ action_controller/filters.rb:624:in `process_without_session_management_support'     C:/ruby/lib/ruby/gems/1.8/gems/actionpack-1.13.2/lib/ action_controller/session_management.rb:114:in `process'     C:/ruby/lib/ruby/gems/1.8/gems/actionpack-1.13.2/lib/ action_controller/base.rb:330:in `process'     C:/ruby/lib/ruby/gems/1.8/gems/rails-1.2.2/lib/dispatcher.rb:41:in `dispatch'     C:/ruby/lib/ruby/gems/1.8/gems/mongrel-1.0.1-mswin32/lib/mongrel/ rails.rb:78:in `process'     C:/ruby/lib/ruby/1.8/thread.rb:135:in `synchronize'     C:/ruby/lib/ruby/gems/1.8/gems/mongrel-1.0.1-mswin32/lib/mongrel/ rails.rb:76:in `process'     C:/ruby/lib/ruby/gems/1.8/gems/mongrel-1.0.1-mswin32/lib/ mongrel.rb:618:in `process_client'     C:/ruby/lib/ruby/gems/1.8/gems/mongrel-1.0.1-mswin32/lib/ mongrel.rb:617:in `process_client'     C:/ruby/lib/ruby/gems/1.8/gems/mongrel-1.0.1-mswin32/lib/ mongrel.rb:736:in `run'     C:/ruby/lib/ruby/gems/1.8/gems/mongrel-1.0.1-mswin32/lib/ mongrel.rb:736:in `run'     C:/ruby/lib/ruby/gems/1.8/gems/mongrel-1.0.1-mswin32/lib/ mongrel.rb:720:in `run'     C:/ruby/lib/ruby/gems/1.8/gems/mongrel-1.0.1-mswin32/lib/mongrel/ configurator.rb:271:in `run'     C:/ruby/lib/ruby/gems/1.8/gems/mongrel-1.0.1-mswin32/lib/mongrel/ configurator.rb:270:in `run'     C:/ruby/lib/ruby/gems/1.8/gems/mongrel-1.0.1-mswin32/bin/ mongrel_rails:127:in `run'     C:/ruby/lib/ruby/gems/1.8/gems/mongrel-1.0.1-mswin32/lib/mongrel/ command.rb:211:in `run'     C:/ruby/lib/ruby/gems/1.8/gems/mongrel-1.0.1-mswin32/bin/ mongrel_rails:243     C:\ruby\bin\mongrel_rails:18     -e:3

The method called to process the posted file does nothing other than render success

def add_image     render :text => 'success', :status => 200 end

If I comment out the 'before_filter :login_required' the error goes away. I did find the following link, http://rubyforge.org/forum/message.php?msg_id=13497, which seems to pertain to the problem but I'm not sure the best way to go about fixing it.

Adding "require 'authenticated_system'" to application.rb solved this problem.