[oXygen-user] XInclude and Relax NG

I am using Version 14.2. I have a Relax NG schema that allows xi:include elements. But the validator does not appear to process the xi:include element prior to validation, as it does not pick up errors arising from the included file. I have checked Enable XInclude processing in the XML Parser settings. Is there anything else to do, or is this just not available (in my version)? Thanks, Tara