QMessageBox::NoButton doesn't work correctly on Windows mobile

copied & pasted from http://lists.trolltech.com/pipermail/qt-wince-interest/2010-May/001120.html

I want to show simple message box on my WM5 device. QMessageBox
class work fine, but it always show two buttons "ok" and "X" (close)
even if I set QMessageBox::NoButton parameter, it still look same. How
to show only one button "ok" or "X". Maybe I'm doing something wrong?
I will be grateful for any suggestions.

QMessageBox::warning(wgt, QString(title), QString(text), QMessageBox::NoButton);