QTreeWidgetItem flags include Qt::ItemIsDropEnabled if created without parent

in http://doc.trolltech.com/latest/qtreewidgetitem.html#flags it says "If the item was constructed with a parent, flags will in addition contain Qt::ItemIsDropEnabled.", what's wrong as QTreeWidgetItem flags also include Qt::ItemIsDropEnabled if created without a parent.
proof:

#include <QTreeWidgetItem>

int main()
{
return QTreeWidgetItem().flags() & Qt::ItemIsDropEnabled;
}