Version:            (using KDE 4.3.1)
OS:                Linux
Installed from:    Ubuntu Packages

http://bugreports.qt.nokia.com/browse/QTBUG-5820

The text on the Tabs isn't shwon.

#include <QtGui>

int main(int argc, char *argv[])
{
	QApplication app(argc, argv);
	QMainWindow mainWindow;

	QDockWidget dockWidget1(QObject::tr("Dock Widget 1"));
	QDockWidget dockWidget2(QObject::tr("Dock Widget 2"));

	mainWindow.setDockOptions(mainWindow.dockOptions() | QMainWindow::VerticalTabs);
	mainWindow.addDockWidget(Qt::LeftDockWidgetArea, &dockWidget1);
	mainWindow.tabifyDockWidget(&dockWidget1, &dockWidget2);

	mainWindow.show();
	return app.exec();
}