DR 09-0209: WML: Custom XML and Smart Tags

[MURATA Makoto (FAMILY Given)]

> As this construct stores custom-defined semantics, it is correct (as implied) 
> that there is no constraint that this attribute contain a URI, or any
> value whatsoever.

I would like to allow IRIs only.  If we allow other values, what will
OOXML application programs do?  They cannot always create namespace 
declarations from the attribute "uri".  They have to check if the given 
attribute value is an IRI.  Moreover, what will they do when the 
value is not an IRI?

Cheers,
Makoto