diff --git a/lib/Crypto/CryptoParam.php b/lib/Crypto/CryptoParam.php
index d694cf2..773f356 100644
--- a/lib/Crypto/CryptoParam.php
+++ b/lib/Crypto/CryptoParam.php
@@ -53,7 +53,7 @@ class CryptoParam
      * @param $min   int Minimal value for parameter.
      * @param $max   int Maximum value for parameter.
      */
-    public function __construct($name, $value, $min, $max)
+    public function __construct($name, $value = null, $min = null, $max = null)
     {
         $this->name = $name;
         $this->value = $value;