Did you ever find a solution?
RIA Team is developing XSD-To-AS3 Class Generator, a simple Air app that allow developers to quickly build any Flex/Flash app XML based.
It takes an XML schema and an XML document and uses it to generate a class library. These classes map directly to data contained in your XML Schema, the generated classes is strongly typed, it forms a kind of template for the developer, ensuring that the data created conforms the underlying XML Schema.
It will be very usefull for quickly work with 3th party API RESTful interface!
Try it @Adobe Air Marketplace
..:: The Ria Team ::..