If your goal is to make twitter boostrap rails work on Windows, there is a version of this that uses static CSS, avoiding the fixed dependency on therubyracer. This will be installed on Windows. You will not have a Less function, but it works on Windows. Try this in your gemfile:
gem 'twitter-bootstrap-rails', :git => "git://github.com/seyhunak/twitter-bootstrap-rails.git", :branch => "static"
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