Dynamic drop down list

I am creating a php and asp page that needs to have the ability to have about 4 drop down menus. The user selects from the first one, and accrording to taht selection the second polulates, then the third and so on..... Where can i find a script that would do that?

I haven't found a quadruple combo script. Try the triple combo scripts here (http://www.google.com/search?hl=en&lr=&ie=UTF-8&oe=UTF-8&q=triple+combo+script%2C+javascript) to get the idea.

http://www.geocities.com/jason_yd/4combo.html