title: Impossible to start Sidekiq
body: <p>After installing Sidekiq on Centos, I try to launch Sidekiq (it's used by Sidekiq), using command:</p>
  
  <pre><code>bundle exec sidekiq
  </code></pre>
  
  <p>But then I get:</p>
  
  <pre><code>tupromail@be-s2534-msl:~/cuttlefish-master$ bundle exec sidekiq
  Warning: the running version of Bundler is older than the version that created the lockfile. We suggest you upgrade to the latest version of Bundler by running `gem install bundler`.
  bundler: command not found: sidekiq
  Install missing gem executables with `bundle install`
  </code></pre>
  
  <p>Point is that Sidekiq was installed, I see it when I run</p>
  
  <pre><code>bundle install
  </code></pre>
  
  <p>I see:</p>
  
  <pre><code>Using sidekiq 3.3.0
  </code></pre>
  
  <p>Also, it seems that Sidekiq executables are there:</p>
  
  <pre><code>tupromail@be-s2534-msl:~/cuttlefish-master$ gem uninstall sidekiq
  Remove executables:
      sidekiq, sidekiqctl
  
  in addition to the gem? [Yn]
  </code></pre>
  
  <p>Any idea?</p>