Redmine

When I create an account for a new redMine user, I give it a default password and ask the user to change it when he or she first logs in. But I don't know if the users actually do that. I'd like to be able to configure redMine such that a new user is forced to create a password the first time he or she logs in. Furthermore, I'd like to limit the amount of time the user has to do this, so that after (say) a week, the account is automatically locked.