title: After logging in as root I get command not found messages
body: <p>when i give the command <code>sudo su</code> or say, <code>sudo -i</code>
  the terminal logs me in successfully as superuser 
  but displays </p>
  
  <pre><code>$: command not found
  $: command not found 
  </code></pre>
  
  <p>Can you help me with how to get rid of this? </p>