Different behaviour of XSD validation on Windows8

Good morning,

I found that XSD validation on Windows8 (probably because of different MSXML6 version?) behaves differently from previous OSes with respect to fixed attributes defined in XSD.

If you define an attribute with a fixed value in XSD and apply it to an XML instance, all validated XML nodes will get that attribute "auto-magically". I used this feature to give a sort of "class attributes" to XML nodes without defining them explicitly in the XML document.

1) if you add a new node of a valid type, on previous versions it will get fixed attributes automatically without doing anything. On Windows8 I have to call validateNode() everytime to apply them

2) if a validate() fails, none of the nodes of the document will get fixed attributes. On previous versions, every valid node get them even if validation has failed

Is there a reason for this? Is it a bug? Is it possible to restore previous behaviour?

Thanks

Davide