diff --git a/includes/common.inc b/includes/common.inc
index 5b250da..5481c7a 100644
--- a/includes/common.inc
+++ b/includes/common.inc
@@ -2489,6 +2489,10 @@ function drupal_clear_js_cache() {
  * We use HTML-safe strings, i.e. with <, > and & escaped.
  */
 function drupal_to_js($var) {
+  if(function_exists('json_encode')) {
+    return str_replace(array('<', '>', '&'), array('\u003c', '\u003e', '\u0026'), json_encode($var));
+  }
+
   switch (gettype($var)) {
     case 'boolean':
       return $var ? 'true' : 'false'; // Lowercase necessary!