diff --git a/pinc/unicode.inc b/pinc/unicode.inc
index 27dd6904d..a27d9ccf0 100644
--- a/pinc/unicode.inc
+++ b/pinc/unicode.inc
@@ -229,7 +229,7 @@ function get_unicode_regex_class($codepoint, $lang = 'php')
     if ($lang == "php") {
         return '\\x{' . $hex . '}';
     } elseif ($lang == "js") {
-        return '\\u{' . $hex . '}';
+        return '\\\\u{' . $hex . '}';
     } else {
         throw new Exception("invalid lang provided: $lang");
     }