diff --git a/lib/GoogleAuthenticator.php b/lib/GoogleAuthenticator.php
index 344c034..0d22e85 100644
--- a/lib/GoogleAuthenticator.php
+++ b/lib/GoogleAuthenticator.php
@@ -57,7 +57,7 @@ public function getCode($secret,$time = null) {
         return $pinValue;
     }
     
-    protected  function hashToInt($bytes, $start) {
+    static protected function hashToInt($bytes, $start) {
         $input = substr($bytes, $start, strlen($bytes) - $start);
         $val2 = unpack("N",substr($input,0,4));
         return $val2[1];