var $tfoot = $('<tfoot></tfoot>');
$($('thead').clone(true, true).children().get().reverse()).each(function(){
    $tfoot.append($(this));
});
$tfoot.insertAfter('table thead');

http://goo.gl/ZcNLf

Snippet may be usefull for cloning table header to the bottom of table.

Snippet will clone all children elements from thead, reverse and insert to tfoot. Example at jsFiddle: <a href="http://jsfiddle.net/xWWYN/">jsFiddle</a>

Cloning table header to the bottom of table with reverse

table

jQuery