diff --git a/Headers/gnustep/gui/NSResponder.h b/Headers/gnustep/gui/NSResponder.h
index 3007ecab8..c897b40f2 100644
--- a/Headers/gnustep/gui/NSResponder.h
+++ b/Headers/gnustep/gui/NSResponder.h
@@ -112,6 +112,7 @@
 - (void) rightMouseDown: (NSEvent*)theEvent;
 - (void) rightMouseDragged: (NSEvent*)theEvent;
 - (void) rightMouseUp: (NSEvent*)theEvent;
+- (void) scrollWheel: (NSEvent *)theEvent;
 
 /*
  * Services menu support