diff --git a/phpseclib/Crypt/RC4.php b/phpseclib/Crypt/RC4.php
index 7cec2e77..8a59518f 100644
--- a/phpseclib/Crypt/RC4.php
+++ b/phpseclib/Crypt/RC4.php
@@ -141,7 +141,7 @@ class Crypt_RC4 extends Crypt_Base
      * @var string
      * @access private
      */
-    var $key = "\0";
+    var $key;
 
     /**
      * The Key Stream for decryption and encryption