Undeclared Identifier: 'GetTypeInfoCount', 'GetTypeInfo', 'GetIDsOfNames', 'Invoke' msxml

I am a BEGINNER to Delphi and Pascal.  I am trying to implement a sax parser but am getting the following compiler errors:

Undeclared Identifier: 'GetTypeInfoCount'
Undeclared Identifier: 'GetTypeInfo'
Undeclared Identifier: 'GetIDsOfNames'
Undeclared Identifier: 'Invoke'

   I have had this problem for days and have been searching for a solution.  I've tried workarounds or different ways to implement a sax parser to no avail.  PLEASE HELP!!!

I'm just trying to implement the IVBSAXContentHandler class. I imported the type library C:\WINDOWS\system32\msxml4.dll.

Below is a basic .pas file to try and get things to compile, any help would be greatly appreciated!  Thanks!

unit Test;

interface

uses MSXML2_TLB;

type

//==============================================================================
// SAX Content Handler
//==============================================================================
  TSAXContentHandler = class(TInterfacedObject, IVBSAXContentHandler)
  public
    constructor Create();
    procedure Set_documentLocator(const Param1: IVBSAXLocator); safecall;
    procedure startDocument; safecall;
    procedure endDocument; safecall;
    procedure startPrefixMapping(var strPrefix: WideString; var strURI: WideString); safecall;
    procedure endPrefixMapping(var strPrefix: WideString); safecall;
    procedure startElement(var strNamespaceURI: WideString; var strLocalName: WideString;
                           var strQName: WideString; const oAttributes: IVBSAXAttributes); safecall;
    procedure endElement(var strNamespaceURI: WideString; var strLocalName: WideString;
                         var strQName: WideString); safecall;
    procedure characters(var strChars: WideString); safecall;
    procedure ignorableWhitespace(var strChars: WideString); safecall;
    procedure processingInstruction(var strTarget: WideString; var strData: WideString); safecall;
    procedure skippedEntity(var strName: WideString); safecall;

    property documentLocator: IVBSAXLocator write Set_documentLocator;

  end;

  implementation
 
//==============================================================================
// SAX Content Handler
//==============================================================================
constructor TSAXContentHandler.Create();
begin

end;

procedure TSAXContentHandler.Set_documentLocator(const Param1: IVBSAXLocator);
begin
end;

procedure TSAXContentHandler.startDocument();
begin
end;

procedure TSAXContentHandler.endDocument();
begin
end;

procedure TSAXContentHandler.startPrefixMapping(var strPrefix: WideString;var strURI: WideString);
begin
end;

procedure TSAXContentHandler.endPrefixMapping(var strPrefix: WideString);
begin
end;

procedure TSAXContentHandler.startElement(var strNamespaceURI: WideString;var strLocalName: WideString;
                       var strQName: WideString; const oAttributes: IVBSAXAttributes);
begin
end;

procedure TSAXContenthandler.endElement(var strNamespaceURI: WideString;var  strLocalName: WideString;
                     var strQName: WideString);
begin
end;

procedure TSAXContentHandler.characters(var strChars: WideString);
begin
end;

procedure TSAXContentHandler.ignorableWhitespace(var strChars: WideString);
begin
end;

procedure TSAXContentHandler.processingInstruction(var strTarget: WideString;var strData: WideString);
begin
end;

procedure TSAXContentHandler.skippedEntity(var strName: WideString);
begin
end;

end.