irb(main):001:0> require "rubygems"
=> false
irb(main):002:0> require "ncurses"
LoadError: no such file to load -- ncurses.so
from /usr/lib/ruby/site_ruby/1.8/rubygems/custom_require.rb:21:in `require__'
from /usr/lib/ruby/site_ruby/1.8/rubygems/custom_require.rb:21:in `require'
from /usr/lib/ruby/gems/1.8/gems/ncurses-0.9.1/lib/ncurses.rb:21
from /usr/lib/ruby/site_ruby/1.8/rubygems/custom_require.rb:27:in `require__'
from /usr/lib/ruby/site_ruby/1.8/rubygems/custom_require.rb:27:in `require'
from /usr/lib/ruby/site_ruby/1.8/rubygems.rb:182:in `activate'
from /usr/lib/ruby/site_ruby/1.8/rubygems.rb:181:in `each'
from /usr/lib/ruby/site_ruby/1.8/rubygems.rb:181:in `activate'
from /usr/lib/ruby/site_ruby/1.8/rubygems/custom_require.rb:26:in `require'
from (irb):2