It seems that the QGraphicsItem interface only exists in Qt 4.6.

svn path=/trunk/KDE/kdebase/workspace/; revision=1031617

desktopchangeosd.h

@@ -86,7 +86,9 @@ class DesktopChangeOSD : public QGraphicsView
 class DesktopChangeItem : public QObject, public QGraphicsItem
     {
     Q_OBJECT
+#if QT_VERSION >= 0x040600
     Q_INTERFACES(QGraphicsItem)
+#endif
     public:
         DesktopChangeItem( Workspace* ws, DesktopChangeOSD* parent, int desktop );
         ~DesktopChangeItem();