title: jQuery tablesorter plugin secondary "hidden" sorting
body: <p>I'm using the jQuery tablesorter plugin and I have a column that contains name of month and year like this</p>
  
  <pre><code>April, 1975
  January, 2001
  </code></pre>
  
  <p>I would like to sort this column as if it were a date column. As I understand it, it is possible to sort the column with some other 'hidden' value, but I just can't seem to find the documentation for that feature. Any help out there?</p>
  
  <p><strong>Update</strong></p>
  
  <p>This fork <a href="http://mottie.github.com/tablesorter/docs/index.html">http://mottie.github.com/tablesorter/docs/index.html</a> of the tablesorter had just what I needed; the ability to store the value to sort by in an attribute, worked really great.</p>