Hash does NOT fully implement mhash. Notably Joomla has 2 lines in helper.php that use an unsupported function: mhash_keygen_s2k(,,,).
Other functions of mhash can be rewritten:
<?php
echo bin2hex(mhash(MHASH_RIPEMD160 ,"my_password"));
echo hash("ripemd160" ,"my_password");
?>
