I am currently developing an xbrl validation software that takes an xml 
instance file and a lot of schemas(xsd files) and  validates it against the 
xsd files.  I am using Visual basic in visual studio 2005. I have managed to 
cycle through the xml file , validate most of the variables, however, i have 
some problems with the namespaces of some attributes. 

For example, in my xml instance file,  it says: 

<xbrldi:typedMember dimension="d-ty:NationalMarketDimension">
        <d-ty:NationalMarket>base metals</d-ty:NationalMarket>
      </xbrldi:typedMember>

In this case, the attribute name is "dimension" and
                  the attribute value is "d-ty:NationalMarketDimension".
The problem is that "dimension" variable is in one namespace, and 
"d-ty:NationalMarketDimension" is in another namespace. i execute the 
following code:

validator.ValidateAttribute(reader.name, reader.NamespaceURI, 
reader.valuevalue, schemainfo)

It validates the name "dimension" correctly with the correct namespace, 
however, the value "d-ty:NationalMarketDimension" should be validated using 
the d-ty namespace, which is another x-sd file. 
The error i get is :
Error Message:The 'dimension' attribute is invalid - The value 
'd-ty:NationalMarketDimension' is invalid according to its datatype 
'http://www.w3.org/2001/XMLSchema:QName' - 'd-ty' is an undeclared namespace.

Can anyone help ?
Thank you