change PAM's encryption from MD5 to SHA?

[l3git.h4cker]

I have Ubuntu 8.04 LTS server, and was wondering how to change PAM and the way it encrypts /etc/shadow's passwords from MD5 to SHA.

Is this possible? If so, how might I do this?

EDIT -> nvm, I found out how to use blowfish

[cdenley]

SHA-512 support in PAM was not present until ubuntu 8.10.
http://ubuntuforums.org/showthread.php?t=924435&page=2