Using xs:alternative in Visual Studio

I am trying to use xs:alternative in an XSD, however Visual Studio 2010 does not recognise xs:alternative as a valid child for xs:element. I am using xmlns:xs="http://www.w3.org/2001/XMLSchema" as my namespace.

I have tried some of the examples I have found online and VS2010 does not like those either. When I run 开发者_JAVA技巧the document through W3C validator, it also does not recognise it.

Am I missing something or is xs:alternative not available yet?

<xs:alternative /> is part of the XSD 1.1 specification.

No Microsoft product yet supports XSD 1.1.