I can not connect to SQL Server 2008 Release 2; from fast CGI PHP on IIS7 and winows server 2008 R2; using Microsoft Drivers for PHP for SQL Server, SQLSRV30.EXE and PHP 5.4.0

I am running FastCGI PHP 5.4.0 x64 on IIS 7.5 on windows server 2008 R2 datacenter

To connect to SQL Server 2008 Release 2, I am trying to use Microsoft Drivers for PHP for SQL Server, SQLSRV30.EXE.

I edited the PHP.ini file,

extension_dir = "ext"

extension=php_pdo_sqlsrv_54_nts.dll

When I issue the phpinfo() command, I get, "without-pdo-mssql"

Error log :  [07-Dec-2012 14:16:20 UTC] PHP Fatal error:  Uncaught exception 'PDOException' with message 'could not find driver' in C:\inetpub\wwwroot\tests\pdo.php:11
Stack trace:
#0 C:\inetpub\wwwroot\tests\pdo.php(11): PDO->__construct('sqlsrv:server=S...', 'sa', 'manager')
#1 {main}
  thrown in C:\inetpub\wwwroot\tests\pdo.php on line 11

Thanks