Declaring an element with an "xml:lang" attribute

Attached is a ZIP file with a sample XML Schema that defines a "text" element with an "xml:lang" attribute.  I guess I thought this should be easy, but the attached solution only works with XSV, TIBCO Extensibility's tools, & MSXML 4.  I cannot get it to work with Xerces 1.4 or the Oracle XDK 9 beta.  Does anyone have a solution that does work for all known validators?  (See attached file: language.zip)

I also couldn't get it to work by just importing the XML namespace without declaring a Schema location; it (for example) causes XSV & MSXML 4 to log an error unless you are lucky enough to have an Internet connection to use to dereference the namespace URI (my laptop often isn't connected).  Perhaps that is a feature, though, rather than the opposite.

I have to admit, it does worry me that it is as difficult as it is just to get an "xml:lang" attribute to work; I know that "xml:*" names are a kind of exceptional case because you can't declare "xmlns:xml" anywhere, but surely they are required by everyone's 80/20 target audience.

     Cheers,
          Tony.
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Anthony B. Coates
(1) Content Distribution Architect - Project Gazelle
(2) Leader of XML Architecture & Design - Chief Technology Office
Reuters Plc, London.
Tony.Coates@reuters.com
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