title: Can't use mongo command, shows command not found on mac
body: <p>I'm using Mac Lion. I was using mongodb version 1.4. I wanted to upgrade to 1.8.5 and I followed <a href="http://shiftcommathree.com/articles/how-to-install-mongodb-on-os-x" rel="noreferrer">http://shiftcommathree.com/articles/how-to-install-mongodb-on-os-x</a> step wise replacing each mongodb-osx-x86_64-1.4.0 by mongodb-osx-x86_64-1.8.5. Everything goes smooth. I tried:</p>
  <pre><code>mongod 
  </code></pre>
  <p>it's ok. I can access localhost:28017
  but,</p>
  <pre><code>mongo
  </code></pre>
  <p>shows command not found</p>
  <p>How can I fix this?</p>