diff --git a/batavia/types/StrUtils.js b/batavia/types/StrUtils.js
index c613ddb8f..0a6bc6aed 100644
--- a/batavia/types/StrUtils.js
+++ b/batavia/types/StrUtils.js
@@ -1,4 +1,5 @@
 var exceptions = require('../core').exceptions
+var constants = require('../core').constants
 var type_name = require('../core').type_name
 var BigNumber = require('bignumber.js').BigNumber
 
@@ -1182,7 +1183,15 @@ function _new_subsitute(str, args, kwargs) {
             // sign
             // alternate form
         if (this.grouping === ',') {
-            throw new exceptions.ValueError.$pyclass("Cannot specify ',' with 's'.")
+            switch (constants.BATAVIA_MAGIC) {
+                case constants.BATAVIA_MAGIC_34:
+                case constants.BATAVIA_MAGIC_35a0:
+                case constants.BATAVIA_MAGIC_35:
+                case constants.BATAVIA_MAGIC_353:
+                    throw new exceptions.ValueError.$pyclass("Cannot specify ',' with 's'.")
+                case constants.BATAVIA_MAGIC_36:
+                    throw new exceptions.ValueError.$pyclass("Cannot specify ',' or '_' with 's'.")
+            }
         }
 
         if (this.sign) {