I want to pass a custom field from my web site to the IPN and have it passed back to my listener. This function does work. The field is an email address but not necessarily the email address of the paypal account of the purchaser. The documentation says I can only have one custom field per IPN and that is fine. But If the enduser purchases 2 different items on the web site, I will be passing 2 custom fields. Which one will it use? Do I need to ask the enduser to enter the email address each time they press the "Add to cart" button?
