On Tue, 03 Oct 2006 20:58:28 +0200, Kelly <lightsolphoenix@gmail.com>  
wrote:

> While skimming through the newest XHTML 2.0 working draft, I noticed  
> that you
> explicitly mention xml:base and xml:lang, but not xml:space and xml:id.   
> I
> assume since XHTML 2.0 is considered XML, all four attributes exist by
> default, but I was curious as to why the former are mentioned and the  
> latter are not.

You must have missed xml:id
http://www.w3.org/TR/xhtml2/mod-core.html#adef_core_xml:id 

As for xml:space, see point 8 in:
http://www.w3.org/TR/xhtml2/conformance.html#s_conform_user_agent 

Since all elements preserve space (on input, not output, which is  
controlled by CSS) xml:space, while allowed, has no effect.

Best wishes,

Steven Pemberton