title: ERROR: Unrecognized command line argument: 'pkg' ( see: 'rvm usage' )
body: <p>I am trying to run </p>
  
  <pre><code>rvm pkg install zlib
  </code></pre>
  
  <p>and I get the following message</p>
  
  <pre><code>ERROR: Unrecognized command line argument: 'pkg' ( see: 'rvm usage' )
  </code></pre>
  
  <p>I installed rvm by running:</p>
  
  <pre><code>sudo apt-get install ruby-rvm
  </code></pre>
  
  <p>I have searched online but I have only found a similar error stating that <strong>package</strong></p>
  
  <p>has changed to <strong>pkg</strong>, but in this case I am using <strong>pkg</strong>. Any ideas? 
  I am using Ubuntu 11.10 x64</p>
  
  <p>Thank you in advance</p>