diff --git a/ko.plus/ko.plus-tests.ts b/ko.plus/ko.plus-tests.ts
index 7dd1053b2..bff291d83 100644
--- a/ko.plus/ko.plus-tests.ts
+++ b/ko.plus/ko.plus-tests.ts
@@ -11,6 +11,9 @@
 
     Version 1.1 - added test for makeEditable
 
+    Version 1.2 - amended callback on commmand.fail() method - accepts response,
+                  status and message values
+ 
     Note: Typescript version 1.4 or higher is required for union types
     and type declarations
 */
@@ -29,8 +32,13 @@ function CommandTests() {
         .done((data: any) => {
         alert("success");
     })
-        .fail((error: string) => {
-        alert(error);
+        .fail((response) => {
+        // dummy
+        return false;
+    })
+        .fail((response, status, message) => {
+        // fail has response, error and text
+        alert(status + message);
     });
 
     // initialize command with options (action only)
diff --git a/ko.plus/ko.plus.d.ts b/ko.plus/ko.plus.d.ts
index dacf6121f..4c9299aee 100644
--- a/ko.plus/ko.plus.d.ts
+++ b/ko.plus/ko.plus.d.ts
@@ -1,8 +1,9 @@
-// Type definitions for ko.plus v0.0.21
+// Type definitions for ko.plus v0.0.24
 // Project: https://github.com/stevegreatrex/ko.plus
 // Definitions by: Howard Richards <https://github.com/conficient>
 // Definitions: https://github.com/borisyankov/DefinitelyTyped
 
+/// <reference path="../jquery/jquery.d.ts" />
 /// <reference path="../knockout/knockout.d.ts" />
 
 /**
@@ -16,6 +17,9 @@
  *
  * Version 1.1 - fixed bug - makeEditable is now a function on .editable
  *               also refactored how the Editable classes inherit to simplify
+ * 
+ * Version 1.2 - amended callback on commmand.fail() method - accepts response,
+ *               status and message values
  */
 
 //
@@ -87,7 +91,7 @@ declare module KoPlus {
         //
         done: (callback: (data: any) => void) => Command;
 
-        fail: (callback: (error: string) => void) => Command;
+        fail: (callback: (response: any, status?: string, statusText?:string) => void) => Command;
 
         always: (callback: Function) => Command;