diff --git a/phpseclib/Crypt/AES.php b/phpseclib/Crypt/AES.php
index 8b1efd4b..a0cecf41 100644
--- a/phpseclib/Crypt/AES.php
+++ b/phpseclib/Crypt/AES.php
@@ -410,7 +410,7 @@ class Crypt_AES extends Crypt_Rijndael {
 
                 $last_pos = strlen($ciphertext) & 0xFFFFFFF0;
                 if ($last_pos) {
-                    $plaintext = mdecrypt_generic($this->demcrypt, substr($ciphertext, 0, $last_pos));
+                    $plaintext.= mdecrypt_generic($this->demcrypt, substr($ciphertext, 0, $last_pos));
                     $this->decryptIV = substr($ciphertext, $last_pos - 16, 16);
                 }
 
@@ -628,4 +628,4 @@ class Crypt_AES extends Crypt_Rijndael {
 }
 
 // vim: ts=4:sw=4:et:
-// vim6: fdl=1:
\ No newline at end of file
+// vim6: fdl=1: