diff --git a/src/plugins/qt4projectmanager/qt4projectconfigwidget.cpp b/src/plugins/qt4projectmanager/qt4projectconfigwidget.cpp
index b999cc31d8a07f237876f9f4656903f14e5d04d6..70360382672afc5c7425e66beea1b81407e34dfd 100644
--- a/src/plugins/qt4projectmanager/qt4projectconfigwidget.cpp
+++ b/src/plugins/qt4projectmanager/qt4projectconfigwidget.cpp
@@ -361,6 +361,9 @@ void Qt4ProjectConfigWidget::updateImportLabel()
             case ProjectExplorer::Task::Warning:
                 type = tr("Warning: ");
                 break;
+            case ProjectExplorer::Task::Unknown:
+            default:
+                break;
             }
             if (!text.endsWith(QLatin1String("br>")))
                 text.append(QLatin1String("<br>"));