Shopping Cart Session Question

Hey all, I'm having a problem with my shopping basket, I know what the problem is but I'm unsure how to solve it. I can add items to the cart no problem and it calculates the total no problem, however when you change the quantity to say "2" then all items in the cart have a quantity of "2" as this is the last entry for quantity entered in to the session. I'm thinking I'm going to have to loop round all the items in the session and check their quantities, if the quantity in the session has to change then change it and move on to the next item while making sure any quantities which are not to change stay equal and so on. If you want to see how its working at the moment go to: www.hostmaster-x.co.uk/homepage.html Any help, advice, tips or tricks welcome. Cheers, Graeme :)