resize of QMessageBox not working?

[Sheng]

I want to change the size of QMessageBox and use resize(int w, int h) function, but it does not make any difference of appearance, any ideas?
Thanks,

[spirit]

QMessageBox has the next flag Qt::MSWindowsFixedSizeDialogHint. so, initially the message box can be resized. but you can try to remove this flag in this case you need to conctruct a dialog by yourself and then call exec() method.

[Sheng]

QMessageBox has the next flag Qt::MSWindowsFixedSizeDialogHint. so, initially the message box can be resized. but you can try to remove this flag in this case you need to conctruct a dialog by yourself and then call exec() method.

still the same, any more suggestion? I can just go ahead to use a dialog, obviously, but feel better if I know why it does not work, thanks.
Here is what I have done:

QMessageBox myMessageBox;
myMessageBox.setText(versionString);
myMessageBox.setStandardButtons(QMessageBox::Close );
myMessageBox.resize(400,200);
myMessageBox.exec();