AI "Felix to check language data type in XML Schema"

(with CC to i18n-core)

.. is done. http://www.w3.org/TR/xmlschema-2/#language does *not* allow 
for empty values: it relies on the pattern
[a-zA-Z]{1,8}(-[a-zA-Z0-9]{1,8})*

I think we (i18n core, i18n ITS or both) should make a comment to the 
XML Schema WG to change this definition, so that it allows for empty values.

Felix