diff --git a/include/wx/string.h b/include/wx/string.h
index cc74023016..d9d59a835c 100644
--- a/include/wx/string.h
+++ b/include/wx/string.h
@@ -377,6 +377,9 @@ public:
     // operator version of GetChar
     wxChar  operator[](int n) const
       { ASSERT_VALID_INDEX( n ); return m_pchData[n]; }
+    // operator version of GetChar
+    wxChar  operator[](unsigned int n) const
+      { ASSERT_VALID_INDEX( n ); return m_pchData[n]; }
     // operator version of GetWritableChar
     wxChar& operator[](size_t n)
       { ASSERT_VALID_INDEX( n ); CopyBeforeWrite(); return m_pchData[n]; }