diff --git a/functions.inc.php b/functions.inc.php
index 12e179d3..fb0e33f5 100644
--- a/functions.inc.php
+++ b/functions.inc.php
@@ -1252,6 +1252,7 @@ function create_salt () {
     return $salt;
 }
 
+/**/ if (!function_exists('hex2bin')) { # PHP around 5.3.8 includes hex2bin as native function - http://php.net/hex2bin
 function hex2bin ($str) {
     $len = strlen ($str);
     $nstr = "";
@@ -1261,6 +1262,7 @@ function hex2bin ($str) {
     }
     return $nstr;
 }
+/**/ }
 
 function to64 ($v, $n) {
     $ITOA64 = "./0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz";