Program does not appear in TaskBar

[Arsenic]

I have a program that seems to (both in XP and Vista) not show on the taskbar when it is launched.

I launch the program but it never shows up on my task bar.

Here's how I initiate my program:

int main(int argc, char *argv[]){
	QApplication app(argc, argv);
        QString stylesheet("");
        app.setStyleSheet(stylesheet);
	PMain pm(0);
	return app.exec();
}
 
PMain::PMain(QWidget *parent) : QWidget(parent) {
	qmw = new QMainWindow(this);
	Log("P system started.");
	pui.setupUi(qmw);
	rows = 10;
	qmw->show();
        connect(pui.actionSave, SIGNAL(triggered()), this, SLOT(s_Save()));
	connect(pui.actionSave_As, SIGNAL(triggered()), this, SLOT(s_SaveAs()));
	connect(pui.actionOpen, SIGNAL(triggered()), this, SLOT(s_Open()));
}

int main(int argc, char *argv[]){
	QApplication app(argc, argv);
        QString stylesheet("");
        app.setStyleSheet(stylesheet);
	PMain pm(0);
	return app.exec();
}

PMain::PMain(QWidget *parent) : QWidget(parent) {
	qmw = new QMainWindow(this);
	Log("P system started.");
	pui.setupUi(qmw);
	rows = 10;
	qmw->show();
        connect(pui.actionSave, SIGNAL(triggered()), this, SLOT(s_Save()));
	connect(pui.actionSave_As, SIGNAL(triggered()), this, SLOT(s_SaveAs()));
	connect(pui.actionOpen, SIGNAL(triggered()), this, SLOT(s_Open()));
}

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I used Designer to make my GUI which is what pui is.
I compile using qmake, make...

I don't know if it is related but there is also an error where when I click on the "X" of the program, it closes but the process doesn't disappear from task manager.

I'm using Qt 4.4 with mingw.