I came across this issue as well. I was passing a hash of hashes to TT and used this method to sort it.
Sample Hash:

%Orders = {};
$Orders{1}{NAME} = 'Bill';
$Orders{1}{STATUS} = 'Complete';
$Orders{2}{NAME} = 'John';
$Orders{3}{STATUS} = 'Pending';
[download]

Sort the hash by key value (orderid) descending and output data from the nested hashes:

<table>
   <tr>
      <th>Order ID</th>
      <th>Name</th>
      <th>Status</th>
   </tr>
[% sortedKEYS = Orders.nsort %]
[% FOREACH skey IN sortedKEYS %]
  <tr>
     <td>[% skey %]</td>
     <td>[% Orders.$skey.NAME %]</td>
     <td>[% Orders.$skey.STATUS %]</td>
  </tr>
[% END %]
</table>
[download]