You get the quote by:
$quote = Mage::getSingleton('checkout/cart')->getQuote();
then you have access to all items:
$quote->getAllItems()
And follow the instructions of the original answer
You get the quote by:
$quote = Mage::getSingleton('checkout/cart')->getQuote();
then you have access to all items:
$quote->getAllItems()
And follow the instructions of the original answer