I need it for my interwiki bot running on the repository test wiki.

(In reply to comment #0)

As per request on wikidata-l please install the sitelinks extension on the demo
system.

http://lists.wikimedia.org/pipermail/wikidata-l/2012-September/001031.html

I requested to install the site_matrix_ extension [[mw:Extension:SiteMatrix]].

Ah doh! Of course. This is what happens when I do this stuff early on a Saturday morning ;-)

Katie has installed the extension now.
(Not closing the bug yet as we'll do this in the next demo session later this week.)

Verified in Wikidata demo time for sprint 16