it looks that pdo_sqlite is built in lsphp5 by default. so no need pdo_sqlite.so at all.
document:
http://www.php.net/manual/en/ref.pdo-sqlite.php
"The PDO_SQLITE PDO driver is enabled by default. To disable, --without-pdo-sqlite[=DIR] may be used"
put phpinfo.php under a folder, and...