Maybe this depends on whether the dragged item is "clickable" like
listbox items and buttons or not , like the Labels in the Tkdnd demo.
Ok, I wrote a second patch that solves this by adding another option to
dnd_start(); if this option is set to True (the default) the user gets
the classic behavior, if set to False the cursor changes when the motion
starts, as in the initial patch. I couldn't figure out a good name for
this option, so I called it "swapcursoronclick", at least the name says
what it is for ^_^