Hello Kamesh,
if you look at the SAP Help link, you see that it is a part of the "Property Metadata Service" (the point one level up). There you see, where you can find the service itself in the portal and if you look at the "Related Areas" you should find "Property Metadata" (at least I do in my 7.31 portal 
).
From there the link you found yourself should guide you well to do the changes you wish.
Regards,
Steffi.