title: Change object type in to datetime64[ns]-pandas
body: <p>I'm analyzing web server log files and having date time in following format. </p>
  
  <pre><code>02/Apr/2013:23:55:00 +0530
  </code></pre>
  
  <p>I'm converting this into pandas date-time format.</p>
  
  <pre><code>df['Time'] = pd.to_datetime(df['Time'])
  </code></pre>
  
  <p>But still it is in the object format. </p>
  
  <pre><code>print df.dtypes
  </code></pre>
  
  <p>Time        object</p>
  
  <p>why it is not changing to <code>datetime64[ns]</code>?</p>
  
  <p>Numpy version</p>
  
  <pre><code>In [2]: np.__version__
  Out[2]: '1.8.0'
  </code></pre>