RE: [xml-dev] Attribute Order

> Maybe I missed the beginning of the thread but have you 
> considered Schematron?

Yes, I think Schematron offers the most flexibility, but also the most
unfamiliarity. :-) 

I was thinking it might not be able to handle undefined elements appearing
in ordered content, but maybe it will. It's been awhile since I looked at
it, so it's time for another perusal. Thanks, Eddie.