If you could change the logo currently set for checkuserWiki to http://checkuser.wikimedia.org/w/img_auth.php/b/bc/Wiki.png .
In the conf file please replace:
'checkuserwiki' => 'http://upload.wikimedia.org/wikipedia/meta/b/bc/Wiki.png',
WITH
'checkuserwiki' => 'http://checkuser.wikimedia.org/w/img_auth.php/b/bc/Wiki.png'
in the 'wgLogo' array
Version: unspecified
Severity: normal
URL: http://checkuser.wikimedia.org/