diff --git a/wp-includes/class-json.php b/wp-includes/class-json.php
index 1e8588db14..417592fb88 100644
--- a/wp-includes/class-json.php
+++ b/wp-includes/class-json.php
@@ -492,7 +492,7 @@ class Services_JSON
                         
                         return ($this->use & SERVICES_JSON_SUPPRESS_ERRORS)
                         ? 'null'
-                        : new Services_JSON_Error(class_name($var).
+                        : new Services_JSON_Error(get_class($var).
                             " toJSON returned an object with a toJSON method.");
                             
                     }
@@ -933,4 +933,4 @@ if (class_exists('PEAR_Error')) {
     
 }
 
-endif;
\ No newline at end of file
+endif;