When a customer buys a downloadable product in Magento, Magento should invoke truelicense.dev.java.net to generate a license file, which can then be delivered as the downloadable product.  

This will involve passing TrueLicense certain details captured in Magento.  Magento v1.3.2.4 or v1.4.0.  Implementation should minimise changes to Magento source code.  

You will need to strong Magento skills, and experience invoking Java from PHP.  Java is running on the same machine.  

Respondents should explain their proposed approach in one or 2 sentences.