On Jul 21, 2011, at 6:25 PM, Dev Guy wrote: > my output is (not sure why I got 1.9.1 in there???) 1.9.1 is the API compatibility version. 1.9.1 is expected. > ["/usr/local/lib/ruby/gems/1.9.1/gems/rdoc-3.8/lib/rdoc/generator.rb", > "/usr/local/lib/ruby/gems/1.9.1/gems/rdoc-3.8/lib/rdoc/generator/markup.rb", > "/usr/local/lib/ruby/gems/1.9.1/gems/rdoc-3.8/lib/rdoc/generator/darkfish.rb", > "/usr/local/lib/ruby/gems/1.9.1/gems/rdoc-3.8/lib/rdoc/generator/ri.rb", > "/usr/local/lib/ruby/gems/1.9.1/gems/horo-1.0.3/lib/rdoc/generator/horo.rb"] You can work around this by uninstalling horo or RDoc 3.8 and reinstalling after completing the upgrade to 1.9.2-p290. I'm not sure how to fix the actual issue in an easy way. The problem is this: RDoc 2.5.8 comes with Ruby 1.9.2 RDoc 2.5.8 will try to load plugins when rdoc/rdoc is loaded. The plugin horo activates the RDoc gem, then requires rdoc/rdoc again redefining methods that won't work with the objects created before the plugin load. Could you add a ticket to redmine.ruby-lang.org and assign it to me?