ODBC Connector to MySQL DB

Hello,

I'm currently trying to connect to a database through a PHP script using the ODBC Connector.  My lines of code are as follows:

$dsn =  "DRIVER={MySQL ODBC 3.51 Driver};" .
"CommLinks=tcpip(Host=localhost);" .
"DatabaseName=handheld;" .
"uid=handheld; pwd=handheld";

$conn = odbc_connect($dsn, "handheld", "handheld");

// Insert statement
$stmt = odbc_prepare($conn, "TRUNCATE TABLE tbl_routing;");

// Check for errors in SQL statement
if (!odbc_execute($stmt))
{
   echo "There has been an error!! - CONNECT";
}

However, I keep getting the error:
Warning: odbc_execute(): SQL error: [unixODBC][MySQL][ODBC 3.51 Driver][mysqld-4.1.12]No database selected, SQL state 3D000 in SQLExecute

I am trying this on a CentOS 4.3 install, php 4.3 and the ODBC 3.51 - MySQL connector installed.

Any more information available on request.  By the way, I need an ODBC connection to the DB as MySQL is only being used temporarily, it will eventually run on a seperate ODBC DB.

Thanks