$(document).ready(function() {
   var $J = jQuery.noConflict();
   var pageContent = $J('#PageContent').height();
   var middle = $J('#middle').height();
   if (pageContent > 337) {
      var heightDiff = pageContent - 337;
      var heightDiffForMiddle = middle + heightDiff;
      $J('#middle').height(heightDiffForMiddle + "px");
   }
});