Marketpress $full_cart object

Hello,
I am trying to hook into the Marketpress shopping cart and would like to be able to edit the product names similar to how variations append $name = $product->post_title . ': ' . $var_names[$variation]; . In stead of appending a variation name, I would like to append a string from a php session variable. When I attempted to edit the $name variable, for the current product being added, it appended the session variable to every product in the cart. Is there a way to append this value to only the product name of the product that was just added?