Strange 'drag' event

Hi

Yesterday I tried to drag an element over the screen using HTML5 drag'n'drop
and detect current mouse position while dragging. I was very surprised that
both in Chrome 4.1 (dev) and Firefox 3.6 it was impossible to do!
'mousemove' event was disabled during dragging and 'drag' event contains
same pageX and pageY properties wherever I move my mouse. I've scanned
through drag'n'drop spec but found nothing about mouse position during drag.

Is this a correct behavior? Or the specification means that it should be
done but browsers implement it incorrectly?

If this behavior is correct, it covers basic drag'n'drop scenarios like
moving product to shopping cart only. But what about scenarios when user has
to drag some kind of handle like an image resize handle or draw anything
with an on-screen pencil? These scenarios urge to have full control on
current mouse position what as I've said before is rather problematic now.

Thanks,
Ivan Suhinin