Thanks for the reply, would you be able to supply a decent link or a quick explanation of how you calculate that? I'm more than happy to admit I'm wrong when I

Thanks for the reply, would you be able to supply a decent link or a quick explanation of how you calculate that? I'm more than happy to admit I'm wrong when I am - the scheme is to make sure all client passwords are different, though not in any way secure against an intelligent attacker - but I am keen to learn more about this, so that as with every discussion on HN, I walk away with a little more knowledge and a little less stupidity.