Holger's Blog A good shell is the best user interface.

WordPress with non-MD5 Passwords

Yes, WordPress is using phpass for users's passwords, but you better change the second parameter to the call of PasswordHash from TRUE to FALSE in the file wp-includes/pluggable.php to get non-MD5/improved hash algorithms.

The algorithm is referenced in the hash stored in the database, so you should be able to change this parameter in every direction while leaving the logins active.

If you change the call to PasswordHash, you also need to set a new password, to propagate the chanes.