diff --git a/phpseclib/Crypt/RC4.php b/phpseclib/Crypt/RC4.php
index 0eb1c2b5..75071d9f 100644
--- a/phpseclib/Crypt/RC4.php
+++ b/phpseclib/Crypt/RC4.php
@@ -353,7 +353,7 @@ class Crypt_RC4 {
             $keyStream = $mode == CRYPT_RC4_ENCRYPT ? 'encryptStream' : 'decryptStream';
 
             if ($this->$keyStream === false) {
-                $this->$keyStream = mcrypt_module_open($this->mode, $this->mcrypt[0], MCRYPT_MODE_STREAM, $this->mcrypt[1]);
+                $this->$keyStream = mcrypt_module_open($this->mode, '', MCRYPT_MODE_STREAM, '');
                 mcrypt_generic_init($this->$keyStream, $this->key, '');
             } else if (!$this->continuousBuffer) {
                 mcrypt_generic_init($this->$keyStream, $this->key, '');