XmlSchemaSet compile() call fills included schema TargetNamespace

Question

Hi everybody,

I have following schemas:

• infrastructureRoot.xsd
  

<?xml version="1.0" encoding="UTF-8" standalone="no"?>
<xs:schema xmlns:xs="http://www.w3.org/2001/XMLSchema" xmlns:mif="urn:hl7-org:v3/mif" xmlns:v3="urn:hl7-org:v3" xmlns:ex="urn:hl7-org/v3-example" xmlns="urn:hl7-org:v3" targetNamespace="urn:hl7-org:v3" elementFormDefault="unqualified">
	<xs:include schemaLocation="datatypes-base.xsd"/>
	<xs:group name="InfrastructureRootElements">
		<xs:sequence>
			<xs:element name="realmCode" type="Norwegian_customer" minOccurs="0" maxOccurs="unbounded"/>
		</xs:sequence>
	</xs:group>
	<xs:attributeGroup name="InfrastructureRootAttributes"/>
</xs:schema>

• datatypes-base.xsd
  

<?xml version="1.0" encoding="UTF-8"?>
<xs:schema xmlns:sch="http://www.ascc.net/xml/schematron" xmlns:xs="http://www.w3.org/2001/XMLSchema" elementFormDefault="unqualified">
<xs:complexType name="customer">
  <xs:sequence>
    <xs:element name="firstname" type="xs:string"/>
    <xs:element name="lastname" type="xs:string"/>
    <xs:element name="country" type="xs:string"/>
  </xs:sequence>
</xs:complexType>

<xs:complexType name="Norwegian_customer">
  <xs:complexContent>
    <xs:restriction base="customer">
      <xs:sequence>
        <xs:element name="firstname" type="xs:string"/>
        <xs:element name="lastname" type="xs:string"/>
        <xs:element name="country" type="xs:string" fixed="Norway"/>
      </xs:sequence>
    </xs:restriction>
  </xs:complexContent>
</xs:complexType>
</xs:schema>

I use following code for load the root schema:

using System;
using System.IO;
using System.Xml;
using System.Xml.Schema;
using System.Diagnostics;

namespace Test
{
	public class DummyReader : TextReader
	{
		public override int Peek()
		{
			return -1;
		}

		public override int Read()
		{
			return -1;
		}

		public override int Read(char[] buffer, int index, int count)
		{
			return 0;
		}

		public override int ReadBlock(char[] buffer, int index, int count)
		{
			return 0;
		}

		public override string ReadToEnd()
		{
			return String.Empty;
		}

		public override string ReadLine()
		{
			return null;
		}
	}

	class Program
	{
		[STAThread]
		static void Main(string[] args)
		{
			

			Func<XmlReader> xmlReaderFactory = () =>
			                                     	{
			                                     		XmlReaderSettings schemaReaderSettings = new XmlReaderSettings{ DtdProcessing = DtdProcessing.Parse};
														XmlTextReader reader = new XmlTextReader(@"InfrastructureRoot.xsd");
			                                     		return XmlReader.Create(reader, schemaReaderSettings);
			                                     	};

			XmlSchema xsd = XmlSchema.Read(xmlReaderFactory(), (sender, eventArgs) => {});
			XmlSchemaSet schemaSet = new XmlSchemaSet();
			schemaSet.ValidationEventHandler += (sender, eventArgs) => Console.WriteLine(eventArgs.Message + " " + eventArgs.Severity);

			try
			{
				try
				{
					XmlReaderSettings schemaReaderSettings = new XmlReaderSettings {DtdProcessing = DtdProcessing.Parse};
					XmlReader schemaReader = XmlReader.Create(new DummyReader(), schemaReaderSettings);
					schemaSet.Add(null, schemaReader);
				}
				catch
				{
					// the only thing this code is needed is to set ProhibitDTD to false
					// there is no acceptable public way to do that
				}

				schemaSet.Add(xsd);
				schemaSet.Compile();
				XmlSchemaInclude external = ((XmlSchemaInclude)xsd.Includes[0]);
				String targetNamespace = external.Schema.TargetNamespace;
				Debug.Assert(targetNamespace == null);
			}
			catch{}
		}
	}
}

After execution "targetNamespace" value equals "urn:hl7-org:v3" , which is not true for original original schema "datatypes-base.xsd" and produce validation errors. Can someone help me with solution?