getOpenFileNames dialog is not centered to the main window

Why the opened dialog is not centered to the main window?

void MainWindow::on_FileOpenAction_triggered()
{
    QStringList fileNames = QFileDialog::getOpenFileNames(
        this, 
        "Open Image",
        QApplication::applicationDirPath(), 
        "Images (*.jpg);;All Files (*.*)"
    );
}

The documentation says that is should work:

This function creates a modal file dialog with the given parent widget. If parent is not 0, the dialog will be shown centered over the parent widget.

I use QT 4.6.3 on Windows XP SP2.

There is either a bug in the Qt or an error in the documentation. If you want a centered dialog, avoid the static functions and create dialog this way:

QFileDialog dialog(
    this, 
    "Open Image",
    QApplication::applicationDirPath(),
    "Images (*.jpg);;All Files (*.*)");
dialog.setFileMode(QFileDialog::ExistingFiles);
QStringList fileNames;
if (dialog.exec())
    fileNames = dialog.selectedFiles();

Note that this uses the Qt's file dialog and not the native file dialog.