I have tried applying the drop down/sub menu in both twentyten raw theme as well as in my child theme. I have reinstalled twentyten to make sure it isn't corrupted, and I have the same problem:
I create a Menu : "Top"
I select the pages I want and add them to this menu. I am able to drag and drop/reorder the menu items, however, when I slide a sub-menu item below its parent, and hit "Save Menu" it bounces back and remains a parent page itself. I have tried this dozens of ties, reapplied, reinstalled, activated TwentyTen instead of the child theme, and nothing works!
The url is:
I have not altered any files in the raw twenty ten theme.