Drag and drop "drag-motion" strangeness

["Miroslav Rajcic" <rajcic sokrates hr>]

I am trying to use "drag-motion" signal to add support for some additional 
drop format testing (using tree view for drop target).

But I noticed the following thing: it appears that "drag-motion" is not 
fired at all when dragging the data from the external source!?
Note that "drag-drop" handler is being correctly called.

Steps to reproduce:
1. Use the example from this page:
   https://live.gnome.org/GnomeLove/DragNDropTutorial
2. When you drag/drop within the application from the left widget to the 
right one (from "coin source" to the "well") "drag-motion" handler
    is correctly called when the mouse pointer with the dragged data is 
over the widget
3. But when dragging from some external applications to the same widget, 
this signal is never fired.
   For example, on Windows, it is not fired when dragging files from Total 
Commander or Windows Explorer (practically any external program I tested)
  On Linux, the signal is fired when dragging the file from Nautilus. When 
dragging the text from Firefox, signal is fired fine for the first drop, but 
drop seem to stop working for any subsequent drop attempt.

Can anyone confirm this ? Is this a known bug, at least on Windows?

Is there a workaround to implement the custom drag/drop formats without 
using "drag-motion" signal?
What I want to implement is to add support for custom formats, namely on 
Windows I want to be able to support OLE drag and drop from Outlook.

Regards,
Miroslav