AX 2009 AIF SalesOrder XML Schema and wierd problems

Hello,

I'm using SalesOrder schema  (http://schemas.microsoft.com/dynamics/2008/01/documents/SalesOrder) in my appication which creates XML files from SalesOrders and tries to validate them with SalesOrder.xsd.

But nothing seems to be valid with that Schema.

Is there bugs with that Schema in AX 2009 environment or what in earth is wrong?

Found some articles from forums where some developers suggested to edit that schema... is that the only reason?

Have anyone of you any ideas what has been commonly wrong with this Schema?

Best Regards.

Mike