title: Bundler throws uninitialized constant Gem::SilentUI (NameError) error after upgrading to Rubygems 1.5.0
body: <p>I ran <code>gem update --system</code> to update to Rubygems 1.5.0 and after every time I run any <code>bundle</code> commands I get:</p>
  
  <p><code>rvm/gems/ruby-1.8.7-p249/gems/bundler-1.0.9/lib/bundler/ui.rb:56: uninitialized constant Gem::SilentUI (NameError)</code></p>
  
  <p>Has anyone else had this issue?</p>