> A quick glance at the XPath spec does not reveal any real 
> advice how to
> handle this. 

It's there in section 5.2.1
> 
> I also miss some advice how to handle the case if the 
> ID-attributes matched
> are not unique, as they should. Saxon appears to pick the 
> first matching
> element from the document, Xalan picks the last.

I think section 5.2.1 is clear that it should pick the first.

Mike Kay
Software AG 

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