Is anyone else out there running Rails 3 and JRuby-Rack, or Jetty and Rails 3? Any trick to it? I'm going insane with some debugging, and at this point I just want to know that it's possible.
These instructions work for me: http://mathias-biilmann.net/2010/2/jruby-and-rails-3-beta-step-by-step
i am using jetty-rails + rails3 for a couple of projects. jetty-rails need to be fixed , require "activesupport" need to be changed to require "active_support" (for activesupport 3.0.3) and you have also do 'require "active_support/all"' to include hash extensions (otherwise symbolize! & reverse_merge method will raise exceptions.. right now trying to fix some jruby-rack issues.. (Rack::Runtime not loaded)..will update once thats done.
来源：https://stackoverflow.com/questions/2278319/anyone-using-jruby-rack-with-rails-3