title: Magento - Add-to-cart querystring replaces cart
body: <p>For some reason, when I have a product in the cart, and then click on an add-to-cart querystring (store.com/store/checkout/cart/add?product=622&qty;=1&super;_group[249]=1) from an email, it creates a whole new cart and loses the previous products.  I guess it creates a whole new session. Is there anyway I can keep the previous products in the cart? I'm using magento 1.4.2.</p>