Extension and Versionning of... namespaces

Hi,

There is a very interesting discussions about managing extensibility  
these days on W3C Mailing-list. I'm giving here a few references. The  
issue has started with a difficulty between xml:id  specification and  
C14N specification, but it has been propagated to a whole namespace  
debate.

Is it possible to add new attributes, new elements to a specification  
without changing the namespace.

For example, you had
	XML 1.1
	xml:lang
later on have been added the attributes:
	xml:base
	xml:id

so we can argue that XML 1.0 specification has been extended with two  
new attributes without changing the xml namespaces.

Another case which is related. XHTML 1.0 has been released with the  
following namespace:
	http://www.w3.org/1999/xhtml
XHTML 1.1 has been issued with the same namespace even if there was an  
addition to the language which is Ruby, a set of elements to deal with  
japanese scripts for example.

References to read on TAG Mailing list (start of threads):
http://www.w3.org/mid/87u0olbhr4.fsf@nwalsh.com
http://www.w3.org/mid/ 
7874BFCCD289A645B5CE3935769F0B52750797@tigger.pureedge.com


-- 
Karl Dubost - http://www.w3.org/People/karl/
W3C Conformance Manager
*** Be Strict To Be Cool ***