diff --git a/src/base-typemaps.i b/src/base-typemaps.i
index d7e502214d..95934b9117 100644
--- a/src/base-typemaps.i
+++ b/src/base-typemaps.i
@@ -147,6 +147,8 @@ typedef char gchar;
             PyList_Append(list, SWIG_NewPointerObj(data, SWIGTYPE_p_Transaction, 0));
         else if (GNC_IS_COMMODITY(data))
             PyList_Append(list, SWIG_NewPointerObj(data, SWIGTYPE_p_gnc_commodity, 0));
+        else if (GNC_IS_COMMODITY_NAMESPACE(data))
+            PyList_Append(list, SWIG_NewPointerObj(data, SWIGTYPE_p_gnc_commodity_namespace, 0));
         else if (GNC_IS_LOT(data))
             PyList_Append(list, SWIG_NewPointerObj(data, SWIGTYPE_p_GNCLot, 0));
         else if (GNC_IS_PRICE(data))