Deleting submenu items does not work as excpected

[rainpoiss]

I have a menu:

Menu1 item submenu item 1 submenu item 2 Menu2 Submenu item 1 Submenu item 2 Submenu item 3 Submenu item 4

When dragging some submenu items from menu 1 to menu two submenu items, and deleteing some sumbenu items from menu2 after that the entire

When deleting some submenu item the entire menu will be deleted