drag and drop in an NSTableView

[Rob Burns]

I have an NSTableView that handles drag and drop. When something is 
dropped on it, its placement is not determined by which row the mouse 
is hovering over when dropped. Because of this, I'd like to have the 
NSTableView 'highlighted' by a square drawn around it or some other 
means, rather than have each row 'highlghted' when the mouse hovers 
over them. What is the easiest way to go about that?

Thanks
Rob