Installation trouble (IIS)

I’m either incredibly stupid, or there’s a bug in the installation of 0.4.5.
Trying a fresh install on IIS 6 with PHP5.x and MySQL 5.x.

I know PHP works and I know MySQL is installed right (used phpmyadmin to create a database for a different site).
The PDO and MySQLi extensions are enabled, and to my knowledge they are working correctly.
Yet, the installer thinks they aren’t (although PDO is checked).

I’m not a real hero when it comes to coding, but I’ve dug up a code example with MySQLi and it worked fine.

So, what can I possibly be doing wrong?

Additionally, I found some PDO sample code, which of course works fine.

<?php
foreach(PDO::getAvailableDrivers() as $driver)
    {
    echo $driver.'<br />';
    }

/*** mysql hostname ***/
$hostname = 'localhost';

/*** mysql username ***/
$username = 'root';

/*** mysql password ***/
$password = 'root';

try {
    $dbh = new PDO("mysql:host=$hostname;dbname=mysql", $username, $password);
    /*** echo a message saying we have connected ***/
    echo 'Connected to database';
    }
catch(PDOException $e)
    {
    echo $e->getMessage();
    }
?>

Results in:
mysql
Connected to database

Apparently this is a known bug.

dev.piwik.org/trac/changeset/1529

And previously answered here.

http://forum.piwik.org/index.php?showtopic=1324