wget http://rubyforge.org/frs/download.php/45905/rubygems-1.3.1.tgz
tar xzf rubygems-1.3.1.tgz
cd rubygems-1.3.1
ruby setup.rb
ここまで快調に来たのですが、ここでエラーが発生しました。
Removing old RubyGems RDoc and ri
Installing rubygems-1.3.1 ri into /usr/lib/ruby/gems/1.8/doc/rubygems-1.3.1/ri
./lib/rubygems/custom_require.rb:31:in `gem_original_require': no such file to load -- rdoc/rdoc (LoadError)
from ./lib/rubygems/custom_require.rb:31:in `require'
from setup.rb:283:in `run_rdoc'
from setup.rb:296
/usr/lib/ruby/gems/1.8/gems/sinatra-0.9.2/lib/sinatra/base.rb:930:in `detect_rack_handler': Server handler (thin,mongrel,webrick) not found. (RuntimeError)
from /usr/lib/ruby/gems/1.8/gems/sinatra-0.9.2/lib/sinatra/base.rb:862:in `run!'
from /usr/lib/ruby/gems/1.8/gems/sinatra-0.9.2/lib/sinatra/main.rb:34
from hello.rb:4