minimize slot does not work in linux.Is it a Bug in Qt?

[anupamgee]

hi,
I have created a frameless QWidget ,then i create a pushbutton and on its clicked signal i called the slot showMinimized() but my frameless widget is not minimizing.
here is the code

widget::widget(QWidget *parent):QWidget(parent)
{
setWindowFlags(Qt::FramelessWindowHint);
QPushButton *button=new QPushButton(this);
button->setGeometry(10,10,20,20);
connect(button,SIGNAL(clicked()),this,SLOT(showMinimized()));
}

widget::widget(QWidget *parent):QWidget(parent)
{
setWindowFlags(Qt::FramelessWindowHint);
QPushButton *button=new QPushButton(this);
button->setGeometry(10,10,20,20);
connect(button,SIGNAL(clicked()),this,SLOT(showMinimized()));
}

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this code runs perfectly in windows but does nt work in linux...Why??
Is there any other way to minimize frameless QWidget in linux.