There's a bug in RTM version with creating attribute using WMI. You'll receive an error similar to the following:
"Verification failed with  errors:
: Failed to verify Discovery
This is an issue with the attribute creation UI.
Export the management pack. Add the reference to Windows Library in the <references> section at the top.
Try XML Notepad to do this. It breaks out the XML for readability.
Then, import the edited XML (management pack) and create the WMI attribute.
PingBack from http://geeklectures.info/2007/12/17/create-new-attribute-using-wmi-rtm/