In the plugin, find each instance of
Code:
$ticker_titles .= '<a href="showthread.php?t='. $ticker['threadid'] .'" title="'. $ticker['title'] .'" target="blank">'. $ticker['title'] .'</a> '. $ticksep.'';
and change the href="showthread... part to a full url.
Example:
Code:
$ticker_titles .= '<a href="http://www.yoursite.com/showthread.php?t='. $ticker['threadid'] .'" title="'. $ticker['title'] .'" target="blank">'. $ticker['title'] .'</a> '. $ticksep.'';