IP ban plugin problem

Hello, I am having issues running IP-Ban Plugin. Can you please help?
Log:

PHP-Error: Warning in functions.php:23 => require_once(classes/SQLite3.class.php): failed to open stream: No such file or directory
[22-May-2012 03:20:27] PHP Fatal error: require_once(): Failed opening required 'classes/SQLite3.class.php' (include_path='.:/usr/share/pear:/usr/share/php') in /home/http://ftp.swx/gameservers.sw…s/functions.php on line 23

Ehm I think Cent OS. PHP version I am not sure

And I dont really get the thread to which you linked. can you please instruct me what do I have to do in order to make this plugin work? thanks!