On http://meta.wikimedia.org/w/api.php?action=sitematrix (same on every other wiki) contains an invalid url syntax at two entries:
<special url="office.wikimedia.org" code="office" private="" />
<special url="test.wikipedia.org" code="test" />
The scheme (http) and the colon is missing, the scheme-specific-part is ok.
Version: unspecified
Severity: major
URL: http://meta.wikimedia.org/w/api.php?action=sitematrix