one of my teammates is trying to join up to our team. But whenever he enters the website he gets this message

" Notice: date_default_timezone_set(): Timezone ID 'America/Indiana/Veva' is invalid in /var/www/ungl.org/class/core.class.php on line 219 Fatal error: Uncaught exception 'Exception' with message 'DateTimeZone::__construct(): Unknown or bad timezone (America/Indiana/Veva)' in /var/www/ungl.org/functions.php:56 Stack trace: #0 /var/www/ungl.org/functions.php(56): DateTimeZone->__construct('America/Indiana...') #1 /var/www/ungl.org/plugin/chatbox/plugin.php(76): fDate('2011-01-20 21:5...') #2 /var/www/ungl.org/class/db.class.php(145): {closure}(0, Array) #3 /var/www/ungl.org/plugin/chatbox/plugin.php(80): DB->getQuery('SELECT * FROM c...', Object(Closure)) #4 /var/www/ungl.org/class/core.class.php(174): chatbox->replace(NULL) #5 [internal function]: {closure}(Array) #6 /var/www/ungl.org/class/core.class.php(183): preg_replace_callback('/\[npanel:(.*)\...', Object(Closure), 'replace('construct() #9 {main} thrown in /var/www/ungl.org/functions.php on line 56"

help would be nice, thanks :D