No such file to load -- stringio (LoadError)?

I recently installed Ruby 1.8.4 on Mac OS X 10.4.7, following
the instructions in

  http://hivelogic.com/articles/2005/12/01/ruby_rails_lighttpd_mysql_tiger

Although irb starts up and runs OK, I am unable to get ri to work
(either within irb or as an external command).

It says:

  >> ri Proc
  /Users/rdm/.irbrc:2: warning:
    Insecure world writable dir /Volumes,
      mode 04177/usr/local/lib/ruby/1.8/yaml.rb:9:in `require':
      no such file to load -- stringio (LoadError)
        from /usr/local/lib/ruby/1.8/yaml.rb:9
        from /usr/local/lib/ruby/1.8/rdoc/ri/ri_descriptions.rb:1
        from /usr/local/lib/ruby/1.8/rdoc/ri/ri_reader.rb:1
        from /usr/local/lib/ruby/1.8/rdoc/ri/ri_driver.rb:5
        from /usr/local/bin/ri:43
  => false

Ignoring the /Volumes nastygram (Hey, it's a mount point!), it
appears that a require is failing. Hmmm...

  >> $:
  => ["/usr/local/lib/ruby/site_ruby/1.8",
      "/usr/local/lib/ruby/site_ruby/1.8/powerpc-darwin8.7.0",
      "/usr/local/lib/ruby/site_ruby",
      "/usr/local/lib/ruby/1.8",
      "/usr/local/lib/ruby/1.8/powerpc-darwin8.7.0",
      "."]

Looks pretty good; let's see if the file is there and readable:

  % cd /usr/local/lib/ruby

  % du -a . | grep stringio.rb
   8 ./1.8/yaml/stringio.rb
  16 ./gems/1.8/gems/actionmailer-1.1.5/lib/action_mailer/
            vendor/tmail/stringio.rb

  % wc ./1.8/yaml/stringio.rb
      83 175 1969 ./1.8/yaml/stringio.rb

At this point, I'm tapped out. Suggestions, anyone?

-r

···

--
http://www.cfcl.com/rdm Rich Morin
http://www.cfcl.com/rdm/resume rdm@cfcl.com
http://www.cfcl.com/rdm/weblog +1 650-873-7841

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