Remove maximize button, why WidgetFlags doesn't work?

[bood]

Qt3+FC5 in main():

Window_Impl mainWindow(0, 0, Qt::WStyle_Customize|Qt::WStyle_Minimize);

but the maximize button is still there on the title bar

unless I use Qt::WStyle_Customize | Qt::WStyle_NoBorder, but this leads to a 'naked' window (no title bar, no border...)