diff --git a/lib/deprecated.php b/lib/deprecated.php
index 4fc4fbfe0..8c53e550b 100644
--- a/lib/deprecated.php
+++ b/lib/deprecated.php
@@ -188,3 +188,55 @@ function datediff($interval, $datefrom, $dateto, $using_timestamps = false)
 
     return $datediff;
 }
+
+
+
+/**
+  * Porting della funzione random_int() per rendere Mpdf retrocompatibile con PHP 5.6
+  */
+if (!function_exists('random_int')) {
+    function random_int($min, $max) {
+        if (!function_exists('mcrypt_create_iv')) {
+            trigger_error(
+                'mcrypt must be loaded for random_int to work',
+                E_USER_WARNING
+            );
+            return null;
+        }
+       
+        if (!is_int($min) || !is_int($max)) {
+            trigger_error('$min and $max must be integer values', E_USER_NOTICE);
+            $min = (int)$min;
+            $max = (int)$max;
+        }
+       
+        if ($min > $max) {
+            trigger_error('$max can\'t be lesser than $min', E_USER_WARNING);
+            return null;
+        }
+       
+        $range = $counter = $max - $min;
+        $bits = 1;
+       
+        while ($counter >>= 1) {
+            ++$bits;
+        }
+       
+        $bytes = (int)max(ceil($bits/8), 1);
+        $bitmask = pow(2, $bits) - 1;
+
+        if ($bitmask >= PHP_INT_MAX) {
+            $bitmask = PHP_INT_MAX;
+        }
+
+        do {
+            $result = hexdec(
+                bin2hex(
+                    mcrypt_create_iv($bytes, MCRYPT_DEV_URANDOM)
+                )
+            ) & $bitmask;
+        } while ($result > $range);
+
+        return $result + $min;
+    }
+}