如何在XSLT 1.0中匹配和处理未知的XML元素？

I have a simply XSLT 1.0 stylesheet, that turns XML documents in XHTML. I really want to be able to "include" the content of an XML file in another when needed. AFAIK it is simply not possible in XSLT 1.0, so I decided to move my processing to a simple Java app that would pre-process the XML, executing the "includes" recursively, and passing it to the default JDK XSLT processor. I have a XML schema that my documents must conform to.I have a simply XSLT 1.0 stylesheet, that turns