Sorry about the big ASCII dump, but this is what I get when trying to require 'rdoc/rdoc'. Any ideas? irb(main):001:0> require 'rdoc/rdoc' E:/Ruby/lib/ruby/1.8/rdoc/parsers/parse_rb.rb:32: warning: already initialized constant EXPR_BEG [several more such warnings, and then...] NameError: uninitialized constant RubyToken::AlreadyDefinedToken from E:/Ruby/lib/ruby/1.8/rdoc/parsers/parse_rb.rb:274:in `def_token' from E:/Ruby/lib/ruby/1.8/rdoc/parsers/parse_rb.rb:301 from E:/Ruby/lib/ruby/1.8/rdoc/parsers/parse_rb.rb:300:in `each' from E:/Ruby/lib/ruby/1.8/rdoc/parsers/parse_rb.rb:300 [from ...] from (irb):1 irb(main):002:0> VERSION => "1.8.2" I'm able to run "rdoc" the command OK. I don't see why the above shouldn't work, because it's the first non transitional-hack line in that command. Thanks, Gavin