diff --git a/src/gtk/app.cpp b/src/gtk/app.cpp
index d78d893db2..e7eef12e68 100644
--- a/src/gtk/app.cpp
+++ b/src/gtk/app.cpp
@@ -508,7 +508,7 @@ bool wxApp::Initialize(int& argc, wxChar **argv)
     //     of the filenames for GTK+ programs, so use it if it is set
     wxString encName(wxGetenv(_T("G_FILENAME_ENCODING")));
     encName = encName.BeforeFirst(_T(','));
-    if (encName == _T("@locale"))
+    if (encName.CmpNoCase(_T("@locale")) == 0)
         encName.clear();
     encName.MakeUpper();
 #if wxUSE_INTL