diff --git a/phpseclib/Crypt/AES.php b/phpseclib/Crypt/AES.php
new file mode 100644
index 00000000..e1683f2a
--- /dev/null
+++ b/phpseclib/Crypt/AES.php
@@ -0,0 +1,422 @@
+<?php
+/* vim: set expandtab tabstop=4 shiftwidth=4 softtabstop=4: */
+
+/**
+ * Pure-PHP implementation of AES.
+ *
+ * Uses mcrypt, if available, and an internal implementation, otherwise.
+ *
+ * PHP versions 4 and 5
+ *
+ * If {@link Crypt_AES::setKeyLength() setKeyLength()} isn't called, it'll be calculated from
+ * {@link Crypt_AES::setKey() setKey()}.  ie. if the key is 128-bits, the key length will be 128-bits.  If it's 136-bits
+ * it'll be null-padded to 160-bits and 160 bits will be the key length until {@link Crypt_Rijndael::setKey() setKey()}
+ * is called, again, at which point, it'll be recalculated.
+ *
+ * Since Crypt_AES extends Crypt_Rijndael, some functions are available to be called that, in the context of AES, don't
+ * make a whole lot of sense.  {@link Crypt_AES::setBlockLength() setBlockLength()}, for instance.  Calling that function,
+ * however possible, won't do anything (AES has a fixed block length whereas Rijndael has a variable one).
+ *
+ * Here's a short example of how to use this library:
+ * <code>
+ * <?php
+ *    include('Crypt/AES.php');
+ *
+ *    $aes = new Crypt_AES();
+ *
+ *    $aes->setKey('abcdefghijklmnop');
+ *
+ *    $size = 10 * 1024;
+ *    $plaintext = '';
+ *    for ($i = 0; $i < $size; $i++) {
+ *        $plaintext.= 'a';
+ *    }
+ *
+ *    echo $aes->decrypt($aes->encrypt($plaintext));
+ * ?>
+ * </code>
+ *
+ * LICENSE: This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
+ * MA  02111-1307  USA
+ *
+ * @category   Crypt
+ * @package    Crypt_AES
+ * @author     Jim Wigginton <terrafrost@php.net>
+ * @copyright  MMVIII Jim Wigginton
+ * @license    http://www.gnu.org/licenses/lgpl.txt
+ * @version    $Id: AES.php,v 1.1 2009-02-16 23:11:01 terrafrost Exp $
+ * @link       http://phpseclib.sourceforge.net
+ */
+
+/**
+ * Include Crypt_Rijndael
+ */
+require_once 'Rijndael.php';
+
+/**#@+
+ * @access public
+ * @see Crypt_Rijndael::encrypt()
+ * @see Crypt_Rijndael::decrypt()
+ */
+/**
+ * Encrypt / decrypt using the Electronic Code Book mode.
+ *
+ * @link http://en.wikipedia.org/wiki/Block_cipher_modes_of_operation#Electronic_codebook_.28ECB.29
+ */
+define('CRYPT_AES_MODE_ECB', 1);
+/**
+ * Encrypt / decrypt using the Code Book Chaining mode.
+ *
+ * @link http://en.wikipedia.org/wiki/Block_cipher_modes_of_operation#Cipher-block_chaining_.28CBC.29
+ */
+define('CRYPT_AES_MODE_CBC', 2);
+/**#@-*/
+
+/**#@+
+ * @access private
+ * @see Crypt_AES::Crypt_AES()
+ */
+/**
+ * Toggles the internal implementation
+ */
+define('CRYPT_AES_MODE_INTERNAL', 1);
+/**
+ * Toggles the mcrypt implementation
+ */
+define('CRYPT_AES_MODE_MCRYPT', 2);
+/**#@-*/
+
+/**
+ * Pure-PHP implementation of AES.
+ *
+ * @author  Jim Wigginton <terrafrost@php.net>
+ * @version 0.1.0
+ * @access  public
+ * @package Crypt_AES
+ */
+class Crypt_AES extends Crypt_Rijndael {
+    /**
+     * MCrypt parameters
+     *
+     * @see Crypt_AES::setMCrypt()
+     * @var Array
+     * @access private
+     */
+    var $mcrypt = array('', '');
+
+    /**
+     * Default Constructor.
+     *
+     * Determines whether or not the mcrypt extension should be used.  $mode should only, at present, be
+     * CRYPT_AES_MODE_ECB or CRYPT_AES_MODE_CBC.  If not explictly set, CRYPT_AES_MODE_CBC will be used.
+     *
+     * @param optional Integer $mode
+     * @return Crypt_AES
+     * @access public
+     */
+    function Crypt_AES($mode = CRYPT_MODE_AES_CBC)
+    {
+        if ( !defined('CRYPT_AES_MODE') ) {
+            switch (true) {
+                case extension_loaded('mcrypt'):
+                    // i'd check to see if aes was supported, by doing in_array('des', mcrypt_list_algorithms('')),
+                    // but since that can be changed after the object has been created, there doesn't seem to be
+                    // a lot of point...
+                    define('CRYPT_AES_MODE', CRYPT_AES_MODE_MCRYPT);
+                    break;
+                default:
+                    define('CRYPT_AES_MODE', CRYPT_AES_MODE_INTERNAL);
+            }
+        }
+
+        switch ( CRYPT_AES_MODE ) {
+            case CRYPT_AES_MODE_MCRYPT:
+                switch ($mode) {
+                    case CRYPT_AES_MODE_ECB:
+                        $this->mode = MCRYPT_MODE_ECB;
+                        break;
+                    case CRYPT_AES_MODE_CBC:
+                    default:
+                        $this->mode = MCRYPT_MODE_CBC;
+                }
+
+                break;
+            default:
+                switch ($mode) {
+                    case CRYPT_AES_MODE_ECB:
+                        $this->mode = CRYPT_RIJNDAEL_MODE_ECB;
+                        break;
+                    case CRYPT_AES_MODE_CBC:
+                    default:
+                        $this->mode = CRYPT_RIJNDAEL_MODE_CBC;
+                }
+        }
+
+        if (CRYPT_AES_MODE == CRYPT_AES_MODE_INTERNAL) {
+            parent::Crypt_Rijndael($this->mode);
+        }
+    }
+
+    /**
+     * Dummy function
+     *
+     * Since Crypt_AES extends Crypt_Rijndael, this function is, technically, available, but it doesn't do anything.
+     *
+     * @access public
+     * @param Integer $length
+     */
+    function setBlockLength($length)
+    {
+        return;
+    }
+
+    /**
+     * Encrypts a message.
+     *
+     * $plaintext will be padded with up to 16 additional bytes.  Other AES implementations may or may not pad in the
+     * same manner.  Other common approaches to padding and the reasons why it's necessary are discussed in the following
+     * URL:
+     *
+     * {@link http://www.di-mgt.com.au/cryptopad.html http://www.di-mgt.com.au/cryptopad.html}
+     *
+     * An alternative to padding is to, separately, send the length of the file.  This is what SSH, in fact, does.
+     * strlen($plaintext) will still need to be a multiple of 16, however, arbitrary values can be added to make it that
+     * length.
+     *
+     * @see Crypt_AES::decrypt()
+     * @access public
+     * @param String $plaintext
+     */
+    function encrypt($plaintext)
+    {
+        if ( CRYPT_AES_MODE == CRYPT_AES_MODE_MCRYPT ) {
+            $this->_mcryptSetup();
+            $this->_pad($plaintext);
+
+            $td = mcrypt_module_open(MCRYPT_RIJNDAEL_128, $this->mcrypt[0], $this->mode, $this->mcrypt[1]);
+            mcrypt_generic_init($td, $this->key, $this->encryptIV);
+
+            $ciphertext = mcrypt_generic($td, $plaintext);
+
+            mcrypt_generic_deinit($td);
+            mcrypt_module_close($td);
+
+            if ($this->continuousBuffer) {
+                $this->encryptIV = substr($ciphertext, -16);
+            }
+
+            return $ciphertext;
+        }
+
+        return parent::encrypt($plaintext);
+    }
+
+    /**
+     * Decrypts a message.
+     *
+     * If strlen($ciphertext) is not a multiple of 16, null bytes will be added to the end of the string until it is.
+     *
+     * @see Crypt_AES::encrypt()
+     * @access public
+     * @param String $ciphertext
+     */
+    function decrypt($ciphertext)
+    {
+        // we pad with chr(0) since that's what mcrypt_generic does.  to quote from http://php.net/function.mcrypt-generic :
+        // "The data is padded with "\0" to make sure the length of the data is n * blocksize."
+        $ciphertext = str_pad($ciphertext, (strlen($ciphertext) + 15) & 0xFFFFFFF0, chr(0));
+
+        if ( CRYPT_AES_MODE == CRYPT_AES_MODE_MCRYPT ) {
+            $this->_mcryptSetup();
+
+            $td = mcrypt_module_open(MCRYPT_RIJNDAEL_128, $this->mcrypt[0], $this->mode, $this->mcrypt[1]);
+            mcrypt_generic_init($td, $this->key, $this->decryptIV);
+
+            $plaintext = mdecrypt_generic($td, $ciphertext);
+
+            mcrypt_generic_deinit($td);
+            mcrypt_module_close($td);
+
+            if ($this->continuousBuffer) {
+                $this->decryptIV = substr($ciphertext, -16);
+            }
+
+            return $this->_unpad($plaintext);
+        }
+
+        return parent::decrypt($ciphertext);
+    }
+
+    /**
+     * Sets MCrypt parameters. (optional)
+     *
+     * If MCrypt is being used, empty strings will be used, unless otherwise specified.
+     *
+     * @link http://php.net/function.mcrypt-module-open#function.mcrypt-module-open
+     * @access public
+     * @param optional Integer $algorithm_directory
+     * @param optional Integer $mode_directory
+     */
+    function setMCrypt($algorithm_directory = '', $mode_directory = '')
+    {
+        $this->mcrypt = array($algorithm_directory, $mode_directory);
+    }
+
+    /**
+     * Setup mcrypt
+     *
+     * Validates all the variables.
+     *
+     * @access private
+     */
+    function _mcryptSetup()
+    {
+        if (!$this->changed) {
+            return;
+        }
+
+        if (!$this->explicit_key_length) {
+            // this just copied from Crypt_Rijndael::_setup()
+            $length = strlen($this->key) >> 2;
+            if ($length > 8) {
+                $length = 8;
+            } else if ($length < 4) {
+                $length = 4;
+            }
+            $this->Nk = $length;
+            $this->key_size = $length << 2;
+        }
+
+        switch ($this->Nk) {
+            case 4: // 128
+                $this->key_size = 16;
+                break;
+            case 5: // 160
+            case 6: // 192
+                $this->key_size = 24;
+                break;
+            case 7: // 224
+            case 8: // 256
+                $this->key_size = 32;
+        }
+
+        $this->key = substr($this->key, 0, $this->key_size);
+        $this->encryptIV = $this->decryptIV = $this->iv = str_pad(substr($this->iv, 0, 16), 16, chr(0));
+
+        $this->changed = false;
+    }
+
+    /**
+     * Encrypts a block
+     *
+     * Optimized over Crypt_Rijndael's implementation by means of loop unrolling.
+     *
+     * @see Crypt_Rijndael::_encryptBlock()
+     * @access private
+     * @param String $in
+     * @return String
+     */
+    function _encryptBlock($in)
+    {
+        // unpack starts it's indices at 1 - not 0.
+        $state = unpack('N*', $in);
+
+        // addRoundKey and reindex $state
+        $state = array(
+            $state[1] ^ $this->w[0][0],
+            $state[2] ^ $this->w[0][1],
+            $state[3] ^ $this->w[0][2],
+            $state[4] ^ $this->w[0][3]
+        );
+
+        // shiftRows + subWord + mixColumns + addRoundKey
+        // we could loop unroll this and use if statements to do more rounds as necessary, but, in my tests, that yields
+        // only a marginal improvement.  since that also, imho, hinders the readability of the code, i've opted not to do it.
+        for ($round = 1; $round < $this->Nr; $round++) {
+            $state = array(
+                $this->t0[$state[0] & 0xFF000000] ^ $this->t1[$state[1] & 0x00FF0000] ^ $this->t2[$state[2] & 0x0000FF00] ^ $this->t3[$state[3] & 0x000000FF] ^ $this->w[$round][0],
+                $this->t0[$state[1] & 0xFF000000] ^ $this->t1[$state[2] & 0x00FF0000] ^ $this->t2[$state[3] & 0x0000FF00] ^ $this->t3[$state[0] & 0x000000FF] ^ $this->w[$round][1],
+                $this->t0[$state[2] & 0xFF000000] ^ $this->t1[$state[3] & 0x00FF0000] ^ $this->t2[$state[0] & 0x0000FF00] ^ $this->t3[$state[1] & 0x000000FF] ^ $this->w[$round][2],
+                $this->t0[$state[3] & 0xFF000000] ^ $this->t1[$state[0] & 0x00FF0000] ^ $this->t2[$state[1] & 0x0000FF00] ^ $this->t3[$state[2] & 0x000000FF] ^ $this->w[$round][3]
+            );
+
+        }
+
+        // subWord
+        $state = array(
+            $this->_subWord($state[0]),
+            $this->_subWord($state[1]),
+            $this->_subWord($state[2]),
+            $this->_subWord($state[3])
+        );
+
+        // shiftRows + addRoundKey
+        $state = array(
+            ($state[0] & 0xFF000000) ^ ($state[1] & 0x00FF0000) ^ ($state[2] & 0x0000FF00) ^ ($state[3] & 0x000000FF) ^ $this->w[$this->Nr][0],
+            ($state[1] & 0xFF000000) ^ ($state[2] & 0x00FF0000) ^ ($state[3] & 0x0000FF00) ^ ($state[0] & 0x000000FF) ^ $this->w[$this->Nr][1],
+            ($state[2] & 0xFF000000) ^ ($state[3] & 0x00FF0000) ^ ($state[0] & 0x0000FF00) ^ ($state[1] & 0x000000FF) ^ $this->w[$this->Nr][2],
+            ($state[3] & 0xFF000000) ^ ($state[0] & 0x00FF0000) ^ ($state[1] & 0x0000FF00) ^ ($state[2] & 0x000000FF) ^ $this->w[$this->Nr][3]
+        );
+
+        return pack('N*', $state[0], $state[1], $state[2], $state[3]);
+    }
+
+    /**
+     * Decrypts a block
+     *
+     * Optimized over Crypt_Rijndael's implementation by means of loop unrolling.
+     *
+     * @see Crypt_Rijndael::_decryptBlock()
+     * @access private
+     * @param String $in
+     * @return String
+     */
+    function _decryptBlock($in)
+    {
+        // unpack starts it's indices at 1 - not 0.
+        $state = unpack('N*', $in);
+
+        // addRoundKey and reindex $state
+        $state = array(
+            $state[1] ^ $this->dw[$this->Nr][0],
+            $state[2] ^ $this->dw[$this->Nr][1],
+            $state[3] ^ $this->dw[$this->Nr][2],
+            $state[4] ^ $this->dw[$this->Nr][3]
+        );
+
+        // invShiftRows + invSubBytes + invMixColumns + addRoundKey
+        for ($round = $this->Nr - 1; $round > 0; $round--) {
+            $state = array(
+                $this->dt0[$state[0] & 0xFF000000] ^ $this->dt1[$state[3] & 0x00FF0000] ^ $this->dt2[$state[2] & 0x0000FF00] ^ $this->dt3[$state[1] & 0x000000FF] ^ $this->dw[$round][0],
+                $this->dt0[$state[1] & 0xFF000000] ^ $this->dt1[$state[0] & 0x00FF0000] ^ $this->dt2[$state[3] & 0x0000FF00] ^ $this->dt3[$state[2] & 0x000000FF] ^ $this->dw[$round][1],
+                $this->dt0[$state[2] & 0xFF000000] ^ $this->dt1[$state[1] & 0x00FF0000] ^ $this->dt2[$state[0] & 0x0000FF00] ^ $this->dt3[$state[3] & 0x000000FF] ^ $this->dw[$round][2],
+                $this->dt0[$state[3] & 0xFF000000] ^ $this->dt1[$state[2] & 0x00FF0000] ^ $this->dt2[$state[1] & 0x0000FF00] ^ $this->dt3[$state[0] & 0x000000FF] ^ $this->dw[$round][3]
+            );
+        }
+
+        // invShiftRows + invSubWord + addRoundKey
+        $state = array(
+            $this->_invSubWord(($state[0] & 0xFF000000) ^ ($state[3] & 0x00FF0000) ^ ($state[2] & 0x0000FF00) ^ ($state[1] & 0x000000FF)) ^ $this->dw[0][0],
+            $this->_invSubWord(($state[1] & 0xFF000000) ^ ($state[0] & 0x00FF0000) ^ ($state[3] & 0x0000FF00) ^ ($state[2] & 0x000000FF)) ^ $this->dw[0][1],
+            $this->_invSubWord(($state[2] & 0xFF000000) ^ ($state[1] & 0x00FF0000) ^ ($state[0] & 0x0000FF00) ^ ($state[3] & 0x000000FF)) ^ $this->dw[0][2],
+            $this->_invSubWord(($state[3] & 0xFF000000) ^ ($state[2] & 0x00FF0000) ^ ($state[1] & 0x0000FF00) ^ ($state[0] & 0x000000FF)) ^ $this->dw[0][3]
+        );
+
+        return pack('N*', $state[0], $state[1], $state[2], $state[3]);
+    }
+}
+
+// vim: ts=4:sw=4:et:
+// vim6: fdl=1:
\ No newline at end of file
diff --git a/phpseclib/Math/BigInteger.php b/phpseclib/Math/BigInteger.php
index a54de1d0..78c6b56a 100644
--- a/phpseclib/Math/BigInteger.php
+++ b/phpseclib/Math/BigInteger.php
@@ -69,7 +69,7 @@
  * @author     Jim Wigginton <terrafrost@php.net>
  * @copyright  MMVI Jim Wigginton
  * @license    http://www.gnu.org/licenses/lgpl.txt
- * @version    $Id: BigInteger.php,v 1.4 2008-05-25 07:28:57 terrafrost Exp $
+ * @version    $Id: BigInteger.php,v 1.5 2009-02-16 23:11:01 terrafrost Exp $
  * @link       http://pear.php.net/package/Math_BigInteger
  */
 
@@ -523,6 +523,20 @@ class Math_BigInteger {
         return $result;
     }
 
+    /**
+     *  __toString() magic method
+     *
+     * Will be called, automatically, if you're supporting just PHP5.  If you're supporting PHP4, you'll need to call
+     * toString().
+     *
+     * @access public
+     * @internal Implemented per a suggestion by Techie-Michael - thanks!
+     */
+    function __toString()
+    {
+        return $this->toString();
+    }
+
     /**
      * Adds two BigIntegers.
      *
@@ -1412,7 +1426,7 @@ class Math_BigInteger {
      *
      * {@link http://groups.google.com/group/sci.crypt/msg/7a137205c1be7d85}
      *
-     * As for why we do all the bitmasking...  strange things can happen when converting from flots to ints. For
+     * As for why we do all the bitmasking...  strange things can happen when converting from floats to ints. For
      * instance, on some computers, var_dump((int) -4294967297) yields int(-1) and on others, it yields 
      * int(-2147483648).  To avoid problems stemming from this, we use bitmasks to guarantee that ints aren't
      * auto-converted to floats.  The outermost bitmask is present because without it, there's no guarantee that