diff --git a/wp-admin/load-scripts.php b/wp-admin/load-scripts.php
index 95a0c0ccf..833677c2d 100644
--- a/wp-admin/load-scripts.php
+++ b/wp-admin/load-scripts.php
@@ -92,6 +92,13 @@ function includes_url() {}
  */
 function wp_guess_url() {}
 
+if ( ! function_exists( 'json_encode' ) ) :
+/**
+ * @ignore
+ */
+function json_encode() {}
+endif;
+
 function get_file($path) {
 
 	if ( function_exists('realpath') )