diff -up qt-everywhere-opensource-src-4.8.2/tools/assistant/tools/assistant/mainwindow.cpp.me qt-everywhere-opensource-src-4.8.2/tools/assistant/tools/assistant/mainwindow.cpp
--- qt-everywhere-opensource-src-4.8.2/tools/assistant/tools/assistant/mainwindow.cpp.me	2012-06-19 12:52:22.740180410 +0200
+++ qt-everywhere-opensource-src-4.8.2/tools/assistant/tools/assistant/mainwindow.cpp	2012-06-19 12:52:51.953194103 +0200
@@ -944,8 +944,7 @@ void MainWindow::updateApplicationFont()
     if (helpEngine.usesAppFont())
         font = helpEngine.appFont();
 
-    const QWidgetList &widgets = qApp->allWidgets();
-    foreach (QWidget* widget, widgets)
+    foreach (QWidget* widget, QApplication::allWidgets())
         widget->setFont(font);
 }