Missing SQL WMI Class

Hello, our new monitoring tool is using the following to get SQL statistics:

Win32_PerfRawData_MSSQLSERVER_SQLServerDatabases

The problem is this class is not present when we try and query with WMI tester. The error is:

0x80041010
 Invalid class

Any idea what needs to be done to add it?

Thanks!

PS.. already tried these to no avail:

http://www.experts-exchange.com/OS/Microsoft_Operating_Systems/Server/2003_Server/Q_26157116.html

http://social.msdn.microsoft.com/Forums/sqlserver/en-US/780d44b9-88e6-41fa-a9e8-81333d8e5dbb/invalid-class-win32perfrawdatamssqlserversqlserverdatabases