diff --git a/src/gui/mainwindow.h b/src/gui/mainwindow.h
index 954e494b3..04de52d06 100644
--- a/src/gui/mainwindow.h
+++ b/src/gui/mainwindow.h
@@ -51,7 +51,6 @@ class TransferListWidget;
 class TransferListFiltersWidget;
 class PropertiesWidget;
 class StatusBar;
-class about;
 class TorrentCreatorDlg;
 class downloadFromURL;
 class LineEdit;