well - you can't, without making major changes that you would be responsible for - and thus unsupported.
You didn't say if you want different OWNERSHIP or PERMISSIONS - too different things actually.
There is no reason that you can't have different owners or settings for subfolders. BUT there are many cases where that also won't work.
I suggest you read this: It provides a very simple fixviewtopic.php?f=17&t=48748