How to add elements and attributes to HTML 4.01 frameset.dtd

<!--
    This is the HTML 4.01 Frameset DTD, which should be
    used for documents with frames. This DTD is identical
    to the HTML 4.01 Transitional DTD except for the
    content model of the "HTML" element: in frameset 
    documents, the "FRAMESET" element replaces the "BODY" 
    element.

          Draft: $Date: 1999/12/24 23:20:08 $

          Authors:
              Dave Raggett <dsr@w3.org>
              Arnaud Le Hors <lehors@w3.org>
              Ian Jacobs <ij@w3.org>

    Further information about HTML 4.01 is available at:

          http://www.w3.org/TR/1999/REC-html401-19991224
-->


<!-- ********** WARNING: CUSTOM DTD **********

  This is a MODIFIED document made from W3C's HTML 4.01 standard DTD loose.dtd
  to allow validation of pages:
    
  - using frames and needing non-standard attributes
    FRAMESPACING, FRAMEBORDER et BORDER inside
    FRAMESET element declaration to suppress
    any spacing between these frames.
  
  Organization providing validation service with custom DTD:
  http://www.htmlhelp.com/tools/validator/index.html.fr
    
  Search for string "STEP" and read instructions there
  to associate this custom DTD to your pages.

  What you have to do: 1st step|2nd step
    
  Author: J.J.SOLARI at yoyodesign.org - date: 2004-01-04
  
-->

<!-- *** STEP 1 ***                                                  
  You have to replace "-//W3C//DTD HTML 4.01 Frameset//EN"           
  in original definition below with the address of this              
  modified DTD to be placed on your site.                            
  For example:                                                       
  !ENTITY % HTML.Version "http://www.example.org/frameset-custom.dtd"
-->                                                                  

<!ENTITY % HTML.Version "-//W3C//DTD HTML 4.01 Frameset//EN">

  -- Typical usage:

    <!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Frameset//EN"
            "http://www.w3.org/TR/html4/frameset.dtd">
    <html>
    <head>
    ...
    </head>
    <frameset>
    ...
    </frameset>
    </html>
-->

<!ENTITY % HTML.Frameset "INCLUDE">

<!-- *** STEP 2 ***                                                  
  You have to replace "-//W3C//DTD HTML 4.01 Transitional//EN"       
  in original definition below with the address of the modified      
  loose.dtd to be placed on your site. You also have to              
  replace PUBLIC identifier with SYSTEM.                             
  For example :                                                      
  !ENTITY % HTML4.td SYSTEM "http://www.example.org/loose-custom.dtd"
-->                                                                  

<!ENTITY % HTML4.dtd PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"

  -- NOTE: This new definition will reference the MODIFIED loose-custom.dtd,     
  which actually contains all definitions of non-standard elements or attributes.
                                                                                 
  As a summary, if you use frames, you will have to place BOTH modified DTDs     
  loose-custom.dtd and frameset-custom.dtd on your site to validate              
  your HTML documents.                                                           

-->

%HTML4.dtd;

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