diff --git a/lib/field_validators/ListField.js b/lib/field_validators/ListField.js
index <HASH>..<HASH> 100644
--- a/lib/field_validators/ListField.js
+++ b/lib/field_validators/ListField.js
@@ -51,11 +51,11 @@ var ListField = createObjectPrototype({
         }
         
         // Check that this is an array
-        if (!Array.isArray(inp)) {
+        if (!(inp instanceof Array)) {
             error = {
                 type: 'type_error',
-                i18nLabel: i18n('isomorphic-schema--list_field_type_error', 'This is not proper list. This is a bug in the application'),
-                message: "This is not proper list. This is a bug in the application"
+                i18nLabel: i18n('isomorphic-schema--list_field_type_error', 'This is not a proper list. This is a bug in the application'),
+                message: "This is not a proper list. This is a bug in the application"
             }
             //console.log(error);
             return error;            
@@ -151,7 +151,7 @@ var ListField = createObjectPrototype({
     
     fromString: function (inp) {
         var _this = this;
-        if (Array.isArray(inp)) {
+        if ((inp instanceof Array)) {
             return inp.map(function (item) {
                 return _this.valueType.fromString(item);
             });
Less strict array check to support Observable array implementations that provide a working instanceof check