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w3.org's content negotiation for skos broken?

From: Jörn Hees <j_hees@cs.uni-kl.de>
Date: Tue, 17 Aug 2010 13:30:30 +0200
To: public-lod@w3.org
Message-Id: <201008171330.30327.j_hees@cs.uni-kl.de>
Hi all,

I'm currently fiddling with a problem related to the content negotiation for 
the SKOS vocabulary:

I need an rdfs:label for skos:subject, which is used quite a lot in DBpedia.
Now the usual lookup of http://www.w3.org/2004/02/skos/core#subject magically 
redirects me to the _most recent_ version of the skos vocabulary (see 
Appendix).
My problem with this: The most recent version does not include a definition of 
skos:subject anymore, so I don't get any label for it.
I tried to find the historical revision manually, but I'm not able to find any 
from February 2004, but only this one:
http://www.w3.org/2004/02/skos/core/history/2004-03-26.rdf
(via http://www.w3.org/2004/02/skos/history )

Perhaps I'm doing something wrong here (please tell me), but currently I think 
the shown behavior is malicious and not according to Linked Data guidelines.
A lot datastores picked up this most recent revision and call it 
http://www.w3.org/2004/02/skos/core (e.g., DBpedia:
http://dbpedia.org/sparql?default-graph-uri=&should-
sponge=&query=select+*+from+%3Chttp%3A%2F%2Fwww.w3.org%2F2004%2F02%2Fskos%2Fcore%3E+where+{+%3Fs+%3Fp+%3Fo+}&format=text%2Fhtml&debug=on&timeout= 
)

Another interesing thing: the current revision includes these namespace defs:
xmlns:skos="http://www.w3.org/2004/02/skos/core#"
xml:base="http://www.w3.org/2004/02/skos/core"
Shouldn't that be 2009/08 ?

Cheers,
Jörn


Appendix:

curl -I -H'Accept: application/rdf+xml' http://www.w3.org/2004/02/skos/core
HTTP/1.1 303 See Other
Date: Tue, 17 Aug 2010 11:07:55 GMT
Server: Apache/2
Location: http://www.w3.org/TR/skos-reference/skos.rdf
Cache-Control: max-age=21600
Expires: Tue, 17 Aug 2010 17:07:55 GMT
Connection: close
Content-Type: text/html; charset=iso-8859-1

curl -I -H'Accept: application/rdf+xml' http://www.w3.org/TR/skos-
reference/skos.rdf
HTTP/1.1 301 Moved Permanently
Date: Tue, 17 Aug 2010 11:08:13 GMT
Server: Apache/2
Location: http://www.w3.org/2009/08/skos-reference/skos.rdf
Cache-Control: max-age=21600
Expires: Tue, 17 Aug 2010 17:08:13 GMT
Connection: close
Content-Type: text/html; charset=iso-8859-1

curl -I -H'Accept: application/rdf+xml' http://www.w3.org/2009/08/skos-
reference/skos.rdf
HTTP/1.1 200 OK
Date: Tue, 17 Aug 2010 11:09:01 GMT
Server: Apache/2
Last-Modified: Tue, 22 Sep 2009 14:05:46 GMT
ETag: "70e3-4742b183e6280"
Accept-Ranges: bytes
Content-Length: 28899
Cache-Control: max-age=21600
Expires: Tue, 17 Aug 2010 17:09:01 GMT
P3P: policyref="http://www.w3.org/2001/05/P3P/p3p.xml"
Connection: close
Content-Type: application/rdf+xml; qs=0.9
Received on Tuesday, 17 August 2010 11:31:01 UTC

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