QListWidget DragOnly

[trallallero]

Hi, I'm using qt 4.6 and I have this problem:
I use a QListWidget object that should be a drag only object.
So, I initialize it in this way:
ui.listwRoles->setAcceptDrops(false);
ui.listwRoles->setDragDropMode(QAbstractItemView:: DragOnly);

But when I drag a text line from the QListWidget and I drop it inside it self, a new text line with the same text is added to the QListWidget.
In few words, it's not a DragOnly object as it accepts drops from itself.

Is there any solution ?
thanks