convert php payment gateway classes into java classes

Hello I have with me a script that acts as a module for wordpress, and enables wordpress to accept one time and recurring payments for a number of payment gateways, including moneybookers and alertpay. I want the moneybookers and alertpay classes to be converted into java classes that will work in Google App Engine (for Java). I have with me an interface for google app engine, your task is to add moneybookers and alertpay as payment options to this google app engine interface. Both one-time and recurring payments must be supported, and Moneybookers and Alertpay should be used. Also, I also have with me a 2-file moneybookers IPN script in PHP... kindly check the wordpress module and see if it supports Moneybookers IPN.(I want the java classes to use Moneybookers IPN). Also if you can add sandbox mode also to the moneybookers/alertpay gateways that would be great... But that is optional. Simple work for a good java coder. Regards, Arvind.