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|18:41, 18 September 2011||Nx||Comment text edited||(Special:ProtectedPages)|
|18:40, 18 September 2011||Nx||New thread created|
So apparently when you create a new protection level you also have to create a message called restriction-level-whatever (it's for Special:ProtectedPages). I didn't know that, so I created MediaWiki:Restriction-level-moderator, but you might want to move it into setupcustomnames (or whatever that function's called) in LocalSettings.php instead where all the others are.