diff --git a/src/gtk/renderer.cpp b/src/gtk/renderer.cpp
index a80ebb065b..30f2e28e4d 100644
--- a/src/gtk/renderer.cpp
+++ b/src/gtk/renderer.cpp
@@ -269,8 +269,7 @@ int wxRendererGTK::GetHeaderButtonHeight(wxWindow *WXUNUSED(win))
 
 int wxRendererGTK::GetHeaderButtonMargin(wxWindow *WXUNUSED(win))
 {
-    wxFAIL_MSG( "GetHeaderButtonMargin() not implemented" );
-    return -1;
+    return 0; // TODO: How to determine the real margin?
 }
 
 
diff --git a/src/osx/carbon/renderer.cpp b/src/osx/carbon/renderer.cpp
index 6d7d52a360..8cc34dbcef 100644
--- a/src/osx/carbon/renderer.cpp
+++ b/src/osx/carbon/renderer.cpp
@@ -251,8 +251,7 @@ int wxRendererMac::GetHeaderButtonHeight(wxWindow* WXUNUSED(win))
 
 int wxRendererMac::GetHeaderButtonMargin(wxWindow *WXUNUSED(win))
 {
-    wxFAIL_MSG( "GetHeaderButtonMargin() not implemented" );
-    return -1;
+    return 0; // TODO: How to determine the real margin?
 }
 
 void wxRendererMac::DrawTreeItemButton( wxWindow *win,