Javascript Attribute Changer in E-Commerce

I am trying to create a e-commerce site that is fairly normal in every way except that when the user is looking at an item, there are several color swatches from which they may select the color that they would like to see their item. When clicked, I would need for the items to load the corresponding pictures of the item loaded using javascript.? I cannot find a plugin that does this in ZenCart or OSCommerce. What I may need if for someone to either to create the plugin or to point me in the direction of an equally impressive E-commerce CMS that has this feature. A good example can be found at the following url: <[login to view URL]>