ruby-on-rails – RailRoad不工作.给我的问题,即/railroad-0.5.0

railroad -M | dot -Tsvg > models.svg
/Users/me/.rvm/gems/ruby-1.9.2-p290/gems/railroad-0.5.0/lib/railroad/app_diagram.rb:54:in `disable_stdout': uninitialized constant AppDiagram::PLATFORM (NameError)
from /Users/me/.rvm/gems/ruby-1.9.2-p290/gems/railroad-0.5.0/lib/railroad/app_diagram.rb:72:in `load_environment'
from /Users/me/.rvm/gems/ruby-1.9.2-p290/gems/railroad-0.5.0/lib/railroad/app_diagram.rb:18:in `initialize'
from /Users/me/.rvm/gems/ruby-1.9.2-p290/gems/railroad-0.5.0/lib/railroad/models_diagram.rb:14:in `initialize'
from /Users/me/.rvm/gems/ruby-1.9.2-p290/gems/railroad-0.5.0/bin/railroad:36:in `new'
from /Users/me/.rvm/gems/ruby-1.9.2-p290/gems/railroad-0.5.0/bin/railroad:36:in `<top (required)>'
from /Users/me/.rvm/gems/ruby-1.9.2-p290/bin/railroad:19:in `load'
from /Users/me/.rvm/gems/ruby-1.9.2-p290/bin/railroad:19:in `<main>'

版本

me$ruby -v
  ruby 1.9.2p290 (2011-07-09 revision 32553) [x86_64-darwin11.1.0]
me$rvm -v
  rvm 1.8.0 by Wayne E. Seguin (wayneeseguin@gmail.com) [https://rvm.beginrescueend.com/]

me$rails -v
  Rails 3.0.10

Every command给了我同样的问题：

铁路-o型号.-M
铁路-a -i -o full_models.dot -M
铁路–M | dot -Tsvg> models.svg
铁路-C neato -Tpng> controllers.png