Bundler throws uninitialized constant Gem::SilentUI (NameError) error after upgrading to Rubygems 1.5.0

Question

I ran gem update --system to update to Rubygems 1.5.0 and after every time I run any bundle commands I get:

rvm/gems/ruby-1.8.7-p249/gems

Answer 1

If you're a bit vague on what bundler actually is and don't want to learn then the very short answer to the question is:

gem install bundler