If you're really keen to do something like this then contacting the author of
this software is something you should do.
According to this website he has managed to create a plugin for winamp that purports to be able to allow the user to:
manage your iPod from within the winamp media library. It supports all kinds of iPods, from the classic first generation iPods, to the iPod shuffle and the latest models.
The project is open source so I would imagine that you should be able to extract the relevant information from this software allowing the Zaurus to act like an iPod.
EDIT: Now I've re-read this post I realise that you've already found this software
Good luck dissecting it!