MySQL PDO connection problems

Hello folks,

Having a bit of trouble getting PDO to connect to my remote MySQL
database...

PHP: 5.2.1, w/ php_mysql, php_pdo, php_pdo_mysql; error reporting is
on, ERROR_STRICT (development server)
OS: Windows 2003 R2 w/ SP2
Web Server: IIS 6, PHP installed as ISAPI
MySQL: 3.23.54 on remote Solaris 9 9/04

I've been connecting to the DB just fine using:

$hd_link = mysql_connect("server","user","passwd");
$hd_db = mysql_select_db("mydb");

But when I try connecting using the PDO:

$link_id = new PDO('mysql:host=server;dbname=mydb', $user, $passwd,
array( PDO::ATTR_PERSISTENT => false));

I get an exception thrown at me: "Unable to connect with Helpdesk
database"

I can't upgrade the MySQL database as it isn't mine and I'm just
"injecting" helpdesk tickets until I complete the new helpdesk.

Any known issues with this situation?

Thanks!