Can't see VirtualBytes in Win32_PerfRawData_PerfProc_Process

Through WMI query: select * from Win32_PerfRawData_PerfProc_Process, can't find the VirtualBytes and VirtualBytesPeak fields in the output, I thought maybe something overrode the class. Followed the steps mentioned in below 3 links, still can't fix the problem, can anyone have a look ? Thanks.

http://support.microsoft.com/kb/2554336

http://technet.microsoft.com/en-us/library/dd363740%28v=ws.10%29.aspx

http://blogs.technet.com/b/yongrhee/archive/2011/10/28/list-of-performance-monitor-related-hotfixes-post-sp1-for-windows-server-2008-r2-sp1.aspx