Name ResolutionErrors - getting NameError on RAILS_END in rails_end.rb When using Desert plugin and Community_Engine

What's an efficient approach to debug NameErrors attributes in Rails?

I am trying to use the desert plugin (0.5.0) and the edge version of Community_Engine. I started from scratch and went through the installation instructions. When I try to start my server, I get this error: "Constant RAILS_END from rails_end.rb not found (NameError)". The problem is I can't find rails_end.rb, nor can I find a link to that google file or an error.

I have verified that the required gems are installed and flowing. I dug around google and desert but didn't find any reference to this constant.

Any ideas? Thanks to

Here's my stack trace:

=> Booting Mongrel
=> Rails 2.3.2 application starting on http://0.0.0.0:3000
/opt/local/lib/ruby/gems/1.8/gems/desert-0.5.0/lib/desert/rails/
dependencies.rb:15:in `load_missing_constant': Constant RAILS_END from
rails_end.rb not found (NameError)
       from /Users/dmr/.gem/ruby/1.8/gems/activesupport-2.3.2/lib/
active_support/dependencies.rb:80:in `const_missing'
       from /Users/dmr/.gem/ruby/1.8/gems/activesupport-2.3.2/lib/
active_support/dependencies.rb:92:in `const_missing'
       from /Users/dmr/dev/lionfold/config/environment.rb:32
       from /Users/dmr/.gem/ruby/1.8/gems/rails-2.3.2/lib/
initializer.rb:111:in `run'
       from /Users/dmr/dev/myapp/config/environment.rb:31
       from /opt/local/lib/ruby/vendor_ruby/1.8/rubygems/
custom_require.rb:31:in `gem_original_require'
       from /opt/local/lib/ruby/vendor_ruby/1.8/rubygems/
custom_require.rb:31:in `require'
       from /Users/dmr/.gem/ruby/1.8/gems/activesupport-2.3.2/lib/
active_support/dependencies.rb:156:in `require'
       from /Users/dmr/.gem/ruby/1.8/gems/activesupport-2.3.2/lib/
active_support/dependencies.rb:521:in `new_constants_in'
       from /Users/dmr/.gem/ruby/1.8/gems/activesupport-2.3.2/lib/
active_support/dependencies.rb:156:in `require'
       from /Users/dmr/.gem/ruby/1.8/gems/rails-2.3.2/lib/commands/
server.rb:84
       from /opt/local/lib/ruby/vendor_ruby/1.8/rubygems/
custom_require.rb:31:in `gem_original_require'
       from /opt/local/lib/ruby/vendor_ruby/1.8/rubygems/
custom_require.rb:31:in `require'
       from script/server:3