Fix encoding

Hi,
I think it should be mb_substr instead of sub_str as that effect the encoding..if we have charectors like ?,?,?..etc.

Could u please fix that ? Line 317 in pts.php file.
$title = substr($title, 0, $position) . '<span class="'.$_classes['cssbox_class'].' pt_splitter-'.$count.'">'.substr($title, $position).'</span>';

Regards