At 16:53 11.03.06 +0100, Peter Boot wrote:
>Since P5 refers us to RFC 3066 when in doubt about how to use the xml:lang 
>attribute (as indeed does the latest version of the XML specification), 
>and since RFC 3066 prescribes
>    2. When a language has both an ISO 639-1 2-character code and an ISO
>       639-2 3-character code, you MUST use the tag derived from the ISO
>       639-1 2-character code.
>the conclusion seems inescapable that when our documents contain multiple 
>languages, some of which have a ISO 639-1 2-character code and some of 
>which don't (such as ancient Greek), we will need to use both two- and 
>three-letter language codes in a single document.

RFC 3066 also states

    If an application has requirements that make the rules here
    inapplicable, the application protocol specification MUST
    specify how the procedure varies from the one given here.

Thus, if you are feeling uncomfortable mixing ISO 639-1 2-character codes 
and ISO 639-2 3-character codes you may follow another rule. Rule 2, which 
you quoted, was obviously written to ensure maximum backward compatibility 
for data transfer between applications. It can be argued that if this is 
not an issue for your encoding project you may modify rule 2 and specify 
how your procedure varies from the default one for example in the TEI header.

Dieter Köhler

Dr. Dieter Köhler, M.A.
Wissenschaftlicher Assistent
Institut für Philosophie und
Studienzentrum Multimedia
Universität Karlsruhe (TH)

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