Unfortunately, it doesn't seem easy to modify the list of recognized interwiki links in MediaWiki. I know in TikiWiki there was an admin page for this, but MediaWiki doesn't have one. All I could find was a page where you can suggest sites to be added into the next release of the code!

Tor Bjornrud wrote: There is not currently a blacklist feature, but it should be easy to hack in. In Title.php there is this function: function userCanRead() { global $wgUser; global $wgWhitelistRead; if( 0 != $wgUser->getID() ) return true; if( !is_array( $wgWhitelistRead ) ) return true; $name = $this->getPrefixedText(); if( in_array( $name, $wgWhitelistRead ) ) return true; # Compatibility with old settings if( $this->getNamespace() == NS_MAIN ) { if( in_array( ":" . $name, $wgWhitelistRead ) ) return true; } return false; } A blacklist will be the opposite of the whitelist: if( in_array( $name, $wgBlacklistRead ) ) return false; Or a namespace blacklist might look like: if( in_array( $this->getNamespace(), $wgBlacklistNs ) ) { return false; } However be careful; MediaWiki is designed for open access, and there may be numerous ways around the poorly tested, little-used access control features. I would not recommend relying on them for any purpose; if you have information you wish to keep private, the best way is to keep it completely separate from a public wiki database and use HTTP authentication to control access at the highest level. -- brion vibber (brion @ pobox.com)