SharePoint Foundation 2010 - SPsite not discovered

Hello,

we are facing some isssues with our SharePoint 2010 farm.

I wanted to target a monitor on Class "SharePoint site in Spweb application", please see "Microsoft SharePoint Foundation 2010 Management Pack Guide.docx"
I was quite surprised that the SPSite objects are not discovered.

MPs installed: "Microsoft SharePoint Foundation 2010", Version 14.0.4744.1000; "Microsoft SharePoint 2010 Products",Version 14.0.4744.1000
Initial configuration was without errors. Discovery for the farm seems to work without errors:
Farms is discovered, Servers, Web Applications, etc.

But teh SP Sites are not. Does somebody know why these objects are missing ?
I exported the MPs.
I didn't find a discovery for Class "Microsoft.SharePoint.Foundation.2010.SPWebApplication.SPSite".

Any solution ? Would be great if I could have the SP sites discovered by these MPs.

Thanks for your help.

Sebastian