I've set up Mediawiki 1.15.1 for a client who has added two users by mistake. They now want to hide these users from the user list.

It seems this is done via the $wgGroupPermissions array with $wgGroupPermissions['suppress']['hideuser'] = true;, but it isn't at all clear what entry this needs for the hiding to work, or whether a new group ('hidden' or whatever) has to be created first with $wgAddGroups['bureaucrat'] = true;.

For now, I've added the two users to be hidden to the 'Oversight' group which explains 'Block a username, hiding it from the public (hideuser)', but they still appear on the Special:ListUsers page.

At a loss as to how the MediWiki arrays alter options displayed in the interface, so far I've added this to LocalSettings.php:

$wgGroupPermissions['suppress']['hideuser'] = true;
$wgAddGroups['supress'] = true;

Or - since they haven't actually added anything to the wiki - could they simply be removed from the MySQL users table - although MediaWiki warns against this?

Has anyone else done this successfully?

Update - this is a hole in MediaWiki admin (although there are workarounds). See this thread on MediaWIki Users and the note to the reply below.