[ruby-it] Curl e Ruby

[Angelbit]

Salve

ho provato a installare la libreria curb ( http://curb.rubyforge.org/ )
con gem (sudo gem install curb ) solo che mi da in putput questo errore:

> 	ERROR: Failed to build gem native extension.
> 
> /usr/bin/ruby1.8 extconf.rb install curb
> extconf.rb:1:in `require': no such file to load -- mkmf (LoadError)
> 	from extconf.rb:1
> 
> 
> Gem files will remain installed in /var/lib/gems/1.8/gems/curb-0.1.4 for inspection.
> Results logged to /var/lib/gems/1.8/gems/curb-0.1.4/ext/gem_make.out

Peche' non funziona?

Grazie