d_func problem

[cookieki]

Hi,All.
I got the problem when subclassing QListWidgetPrivate.

#include <private/qlistwidget_p.h>
...
QItemSelectionModel::SelectionFlags QListWidgetPrivateEx::selectionCommand(const QModelIndex &index,const QEvent *event) const
{
	Q_D(const QAbstractItemView);
...
}

#include <private/qlistwidget_p.h>
...
QItemSelectionModel::SelectionFlags QListWidgetPrivateEx::selectionCommand(const QModelIndex &index,const QEvent *event) const
{
	Q_D(const QAbstractItemView);
...
}

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compiler(vs2003) shows error.
'd_func': identifier not found, even with argument-dependent lookup
What's the problem?