Deprecated language tags and document conformance

I'd expect deprecated RFC 4646 language tags or subtags to render a  
document non-conforming for the purpose of overall HTML5 document  
conformance. Is my expectation correct?

On a related note, the grandfathered language tag i-default seems  
inappropriate for HTML5 lang or XHTML5 xml:lang, since these  
attributes can take the non-RFC4646 value "" to indicate that the  
natural language is unknown. Should lang='i-default' (or xml:lang='i- 
default') be taken to render the document non-conforming?

Henri Sivonen

Received on Thursday, 18 October 2007 12:40:19 UTC