Hi,
I just noticed a bug in the RDF live exports of Wikidata: they still use the base URI http://wikiba.se/ontology-beta# for all Wikidata vocabulary terms. The correct base URI would be http://wikiba.se/ontology#. I guess this has been forgotten and never got noticed yet (not sure if there are consumers of the live exports).
The SPARQL query service uses the correct URIs in its example queries and data. The URIs in the ontology documents at wikiba.se are also correct, so this only seems to affect the PHP code.
Cheers,
Markus
[1] wikiba.se/ontology