Privacy concern: different FOAF file depending on what website is asking

Hello,

During the 5th step of actual spec, the WebID verifier contact a distant
webserver to get the FOAF file.

Obviously, some people don't want to share the same pieces of information
depending on who is asking.
For instance :
- For facebook.com I just want to share my first and last name.
- For twitter.com I want to share my friend list
- For linkedin.com I don't want to share anything
- A more common rules for website I don't know.


Is there any work (such as an ontology) done related to this?  I've
searched in the list archive without success.


Thanks.

Best regards,
--
Baptiste Lafontaine
Etudiant Télécom SudParis
CV : http://magnetik.org/fr/curriculum-vitae/
Mobile : +33 (0) 6 75 30 15 33