[thelist] Custom DTD for HTML documents

[Hershel Robinson]

Here, Jacques Distler shows a method of extending the XTHML DTD to allow the
target attribute on an anchor tag:

http://golem.ph.utexas.edu/~distler/blog/files/zeldman.html

There are 2 other methods of extending the DTD mentioned here:
http://dionidium.com/2004/05/xhtml-tests

For my purposes, Distler's method seems ideal, as there is more than one
attribute I want to add to the W3C's DTD and I have a whole slew of pages to
which I want to assign this extended DTD.

My question is, does anyone have any resources which can help me extend the
DTD? This page:
http://www.w3.org/TR/xhtml-modularization/

and its fellow pages there are a bit much for me. I am trying to understand
them, but I am not having a tremendous amount of success just yet.

All I want to do is write my own module to extend the XHTML DTD to allow a
few custom attributes to certain tags. The issue which seems to be in the
way is defining the namespace of the module. I think.

Any help is appreciated.

Thanks,
Hershel