--- /Users/yannick/Downloads/drupal-6.22/includes/common.inc
+++ /Users/yannick/Desktop/common_patched.inc
@@ -2489,6 +2489,10 @@
  * 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!