Your PHP configuration restricts SourceBans to a certain amount of memory.
When viewing the Banlist it tries to lookup the according country for the IP. This is done by loading a ~7MB database file into the memory.

There are several ways to solve this.

• Remove the '//' in front of this line in your config.php: define('SB_MEM', '128M');
• Ask your webhost to increase the PHP 'memory_limit' setting.
• If it still doesn't show up, check the box for 'No Country Research' in your webpanel settings page.