You can't switch this on from the Saxon command line, you have to do a bit of Java coding. Basically, you supply a SAXSource as the input to Saxon, initializing the SAXSource with an XMLReader that identifies the Xerces parser, and set the appriopriate feature(s) on the XMLReader, as described at
Michael Kay

From: [] On Behalf Of Bhavin Kamani
Sent: 08 November 2005 03:12
Subject: [saxon] Using XInclude with Saxon 8.6

Can I use xinclude with saxon 8.6. I believe the latest version of xerces (2.7.1)has support for xinclude. Is it possible to use xerces 2.7.1 as the Source parser. If so how do I enable xinclude related xerces features?
Thanks in advance
Bhavin Kamani