static function create($value = '', $type = self::EMAIL, $global = self::IMPORT_LOCAL)
 {
     if (!eZRobinsonListEntry::inList($value)) {
         $rows = array('value' => $value, 'type' => $type, 'global' => $global);
         $entry = new eZRobinsonListEntry($rows);
         $entry->store();
         return $entry;
     } else {
         return null;
     }
 }