Description:
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A PDO::__construct() throwed an exception when I tried to open sqlite database, seem no driver for sqlite.

My dsn is work fine in PHP 5.0.5.

Reproduce code:
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<?php
$dbh = new PDO('sqlite:D:/DB/SQLite/test.db3');
?>

Expected result:
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$dbh is a PDO object.

Actual result:
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Fatal error: Uncaught exception 'PDOException' with message 'could not find driver'