177566 PHP/SQL

You see how on [login to view URL] if you click on Title, Username, Created, Replies, and Views, it reorders the list in asc order, then if you click again it orders it in desc order. I need something like this for WordPress 2.2.2. I have the Custom Field GUI installed ([login to view URL]), and on my blog it lists the meta_key and meta_values. I need it so if I click on the meta_key, it lists the meta_values that are under that meta_key in asc order, and if I click it again it lists the values in desc order.