diff -r 5dc02b23752f -r 3e2da88830cd demos/mainwindow/mainwindow.cpp
--- a/demos/mainwindow/mainwindow.cpp	Tue Jul 06 15:10:48 2010 +0300
+++ b/demos/mainwindow/mainwindow.cpp	Wed Aug 18 10:37:55 2010 +0300
@@ -81,6 +81,8 @@
 #endif
     ;
 
+Q_DECLARE_METATYPE(QDockWidget::DockWidgetFeatures)
+
 MainWindow::MainWindow(const QMap<QString, QSize> &customSizeHints,
                         QWidget *parent, Qt::WindowFlags flags)
     : QMainWindow(parent, flags)
@@ -274,6 +276,8 @@
 
 void MainWindow::setupDockWidgets(const QMap<QString, QSize> &customSizeHints)
 {
+    qRegisterMetaType<QDockWidget::DockWidgetFeatures>();
+
     mapper = new QSignalMapper(this);
     connect(mapper, SIGNAL(mapped(int)), this, SLOT(setCorner(int)));