diff --git a/nml/expression/base_expression.py b/nml/expression/base_expression.py
index 92bdc60a..b6580ad2 100644
--- a/nml/expression/base_expression.py
+++ b/nml/expression/base_expression.py
@@ -92,7 +92,7 @@ def supported_by_action2(self, raise_error):
         @return: True if this expression can be calculated by advanced varaction2.
         """
         if raise_error:
-            raise generic.ScriptError("This expression is not supported in a switch-block", self.pos)
+            raise generic.ScriptError("This expression is not supported in a switch-block or produce-block", self.pos)
         return False
 
     def supported_by_actionD(self, raise_error):