diff --git a/src/mac/carbon/choice.cpp b/src/mac/carbon/choice.cpp
index d4268c6e97..f2173eb03c 100644
--- a/src/mac/carbon/choice.cpp
+++ b/src/mac/carbon/choice.cpp
@@ -217,6 +217,12 @@ unsigned int wxChoice::GetCount() const
 
 int wxChoice::FindString( const wxString& s, bool bCase ) const
 {
+#if !wxUSE_STL
+    // Avoid assert for non-default args passed to sorted array Index
+    if ( HasFlag(wxCB_SORT) )
+        bCase = true;
+#endif
+
     return m_strings.Index( s , bCase ) ;
 }