Proposal for xml:lang

This is my action item
http://www.w3.org/2006/07/21-i18nits-minutes.html#action03 .
"Felix to draft s.t. about xml:lang in general":
My text proposal, in a separate, non-normative subsection about xml:lang :

The language information data category provides for rules to be
expressed at a global level because it is unnecessary locally. Locally
users are able to use xml:lang (which is defined by XML) or an attribute
specific to the format in question (as in Example 33).

xml:lang is the preferable means of language identification. To easy the
usage of xml:lang, a declaration for this attribute is part of the
non-normative XML DTD and XML Schema document for ITS markup
declarations. There is no declaration of xml:lang in the non-normative
RELAX NG document for ITS, since in RELAX NG it is not necessary to
declare attributes from the XML namespace.

Applying the langRule data category to xml:lang attributes using global
rules is not necessary, since xml:lang is already defined in terms of
RFC 3066 or its successor".

This relates to issue 1, 4, 41, 46. I think they could be resolved with
the proposal.

Issue 48 "We feel that there should be a note in the specification that
says that it is implied/understood that xml:lang represents language
information wherever it appears.":
I'm not sure if we can say this. In i18n core, we currently discuss
whether xml:lang could be regarded as the core / the trigger of locale
information. It is true that this functionality of xml:lang is only
useful if language information is in the center of the locale (that is,
not e.g. for time zone information, and only to a certain extend for
currency information). However, the locale related functionality of
xml:lang is still different than representation of language information,
so I think we should say:
"xml:lang represents language information wherever it appears. However,
sometimes this information is used for functionality which goes beyond
language identification, e.g. identification of the locale."

Cheers,

Felix