Wouldn't this be much nicer?

<?php
    $td 
= new Mcrypt('tripledes''cfb');

    echo 
$td->name;

    echo 
$td->is_block_algorithm;
    echo 
$td->block_size;

    echo 
$td->iv_size;
    echo 
$td->key_size;

    
$iv $td->generate_iv();
    
/* or */
    
$iv mcrypt::creat_iv($size);
    
$td->set_iv($iv);

    
$td->set_key('secret_key'MCRYPT_HASH); /* or MCRYPT_PAD */

    
$td->init(); /* optional, only required for multiple encryptions */
    
$crypt $td->encrypt('secret text');

    
$td NULL;
?>