cached_model broken in Edge Rails

Hello,

I'm getting the following stack trace when I start Edge Rails (5384) with cached_model 1.3.1. If i switch to Rails 1.1.6, it works fine. Any help will be appreciated.

$ ./script/server => Booting Mongrel (use 'script/server webrick' to force WEBrick) => Rails application started on http://0.0.0.0:3000 => Call with -d to detach => Ctrl-C to shutdown server ** Starting Mongrel listening at 0.0.0.0:3000 ** Starting Rails with development environment... Exiting ./script/../config/../vendor/rails/activesupport/lib/active_support/dependencies.rb:256:in `load_missing_constant': uninitialized constant Rails::VERSION (NameError)         from ./script/../config/../vendor/rails/activesupport/lib/active_support/dependencies.rb:360:in `const_missing'         from /usr/lib/ruby/gems/1.8/gems/cached_model-1.3.1/lib/cached_model.rb:77         from /usr/local/lib/site_ruby/1.8/rubygems/custom_require.rb:33:in `gem_original_require'         from /usr/local/lib/site_ruby/1.8/rubygems/custom_require.rb:33:in `require'         from ./script/../config/../vendor/rails/activesupport/lib/active_support/dependencies.rb:400:in `require'         from script/../config/../config/environments/development.rb:24:in `load_environment'         from ./script/../config/../vendor/rails/railties/lib/initializer.rb:190:in `load_environment'         from ./script/../config/../vendor/rails/activesupport/lib/active_support/core_ext/kernel/reporting.rb:11:in `silence_warnings'          ... 24 levels...         from ./script/../config/../vendor/rails/activesupport/lib/active_support/dependencies.rb:400:in `require'         from ./script/../config/../vendor/rails/railties/lib/commands/server.rb:39         from ./script/server:3:in `require'         from ./script/server:3