This is what happened when I want to install rmagick gem.
username@username-desktop:~$ sudo gem install rmagick Bulk updating Gem source index for: http://gems.rubyforge.org/ ERROR: could not find rmagick locally or in a repository
What the hell… After some googling I found that RubGems 1.1.x is buggy and and update to RubyGems 1.2 is necessary. To learn your RubyGems version:
username@username-desktop:~$ gem -v 1.1.0