Pastebin is so 2002 (they even admit it). :P You should trim down your code to the section that isn't working and include markup (without markup and CSS, how could anyone tell what is happening with addClass?) at jsfiddle.net or mooshell.net.
addClass certainly works in MT 1.12/IE 8: http://jsfiddle.net/ygqge/ You'll have to put up a counterexample. -- Sandy
