[xwiki-devs] Using XInclude for parsing XAR documents?

Hello fellow developers, in order for the current source file to be a real source file outside of the XML of the xar, e.g. a .properties, a .vm, a .groovy, it would be enough to enable XInclude on the parser that reads the XML document. Which source should I look into? Also, where for xwiki 1.5? thanks in advance paul