[rules-users] Roll Back Rule / Rule Transactions?

I am working on rules for an online shopping cart. Depending on the products in the cart, the customer may get certain discounts. If cart contains a TV, add a free VCR. I can apply these rules, but what about rolling them back? So in the example above, the rule automatically added a free VCR because the cart contained a TV. If the customer removes the TV, I need to roll back the VCR rule and also remove the VCR from the cart. Does anyone know how to do this? Is it possible? Matt Johnston Manager of Internet Content Publishing Group of America p: 615-468-6053 f: 615-468-6153