QToolBar isn't dockable on Zaurus, QToolBar isn't dockable on Zaurus Options

[simonqu]

I'm developing an application for sharp zaurus 5600 and encontered a QToolBar related problem. The program is working fine in my PC. When tranfered to PDA, the QToolBar isn't dockable. Any body here can help me?
Thanks
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Here enclosed the program
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#include <qapplication.h>
#include <qtoolbar.h>
#include <qwhatsthis.h>

class SmMainWin_QT:pulic QMainWindow
{
public:
SmMainWin_QT();
}
SmMainWin_QT::SmMainWin_QT():QMainWindow(0, "test")
{
resize(235, 315);
QToolBar * tool_bar = newQToolBar(this);
addToolBar(tool_bar, Minimized);
(void)QWhatsThis::WhatsThisButton(tool_bar);
}

int main(int argc, **argv)
{
QApplication app(argc, argv);
SmMainWin_QT* mainWin = new SmMainWin_QT();
app.setMainWidget(mainWin);
mainWin->show();
return app.exec();
}