Attribute Exchange external reference?

[=nat]

Hi. 

I am kind of new to this field, and this topic may have been discussed
before, but since a Google search on [site:http://openid.net/pipermail/
attribute exchange external reference ] did not match anything, let me bring
this up. 

On scanning http://openid.net/specs/openid-attribute-exchange-1_0-05.html,
which looked pretty good, a question "Would it be even nicer if we could
have a hook for external data source?" came up to my mind. 

For example, if we could write something like 

openid.ax.type.externalref=http://example.com/schema/industry_specific_data
openid.ax.value.externalref=http://example.com/specific_data.xml

in the response, and have the client fetch the document from http://example.
com/specific_data.xml (if it understands the schema type of it), it would be
useful in bringing OpenID framework and something else together. 

I initially thought that it could be done in the New Attribute Process
[http://openid.net/specs/openid-attribute-types-1_0-02.html#anchor6], but
since it requires fetching of external document and thus changes the client
behavior, I brought up this here. 

Any thought? 

=nat