chasetoys@LilArooni:/usr/lib/ruby/gems/1.8$ sudo gem install gettext
Select which gem to install for your platform (i486-linux)
 1. gettext 1.9.0 (ruby)
 2. gettext 1.9.0 (mswin32)
 3. gettext 1.8.0 (ruby)
 4. gettext 1.8.0 (mswin32)
 5. gettext 1.7.0 (mswin32)
 6. gettext 1.7.0 (ruby)
 7. gettext 1.6.0 (mswin32)
 8. gettext 1.6.0 (ruby)
 9. gettext 1.5.0 (ruby)
 10. gettext 1.5.0 (mswin32)
 11. gettext 1.4.0 (mswin32)
 12. gettext 1.4.0 (ruby)
 13. gettext 1.3.0 (mswin32)
 14. gettext 1.3.0 (ruby)
 15. gettext 1.2.0 (mswin32)
 16. gettext 1.2.0 (ruby)
 17. gettext 1.1.1 (ruby)
 18. gettext 1.1.1 (mswin32)
 19. gettext 1.1.0 (mswin32)
 20. gettext 1.1.0 (ruby)
 21. gettext 1.0.0 (mswin32)
 22. gettext 1.0.0 (ruby)
 23. Cancel installation
> 1
Building native extensions.  This could take a while...
extconf.rb:12:in `require': no such file to load -- mkmf (LoadError)
        from extconf.rb:12

ERROR:  While executing gem ... (RuntimeError)
    ERROR: Failed to build gem native extension.
Gem files will remain installed in /usr/lib/ruby/gems/1.8/gems/gettext-1.9.0 for inspection.


Results logged to /usr/lib/ruby/gems/1.8/gems/gettext-1.9.0/ext/gettext/gem_make.out
chasetoys@LilArooni:/usr/lib/ruby/gems/1.8$