that works if you are usign the berkeley database - which you really shouldn't be. MYSQL is far more stable, and every time berkeley is upgrade you site will break till you run the upgrade.
Also if you switch hosts and your new host uses a older version of berkeley, there's no way to get access to your database.
Oh, if you're not usign berkeley and this didn't fix your problem, look into a program call MT Medic. It's a simple upload and it can access your install and create a new users and other useful things.