Did you install rubygems like this?
" 3.1 Installing RubyGems
Get it from RubyForge (http://rubyforge.org/frs/?group_id=126
) and run (as root, if appropriate and necessary)
Itâs easy. It installs the required library files and the gem command. This command gives us the power to do everything else in this document, except distribute gems (for now!)."
From gem manual at:
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