When you sell pin codes or software licence codes using PHP-KeyCodes, you may want the customer to enter in some text during purchase which is returned to you in the purchase information. This might be the type of cellphone, or some other information that you require for you records.
PayPal has a field called ‘custom’ which is a pass through field where any data entered into the field will be passed unchanged to PayPal and returned inside the IPN data.
In PHP-KeyCodes, entering text into the custom field is returned with the IPN payment details and the data is stored in the tblsaleshistory table along with all the other PayPal details and the purchased licence codes.
To use this feature all you need to do is add an html input text field as shown in http://www.withinweb.com/phpkeycodes/handbuttons.php The maximum number of characters that can be entered is 255.