a possible password system

user.rb

attr_accessor :new_password

validates_presence_of :new_password, :on => :create
validates_length_of :new_password, :minimum => 6, :allow_nil => true, :allow_blank => true, :unless => :new_password.blank?
validates_confirmation_of :new_password

before_save :set_encrypted_password

def set_encrypted_password
  write_attribute(:password, Client.encrypt_password(@new_password)) unless @new_password.nil? || @new_password.blank?
end

def self.encrypt_password(password)
  Digest::SHA1.hexdigest("something_random_goes_here_#{password}")
end

def self.authenticate(email, password)
  find_by_email_and_password_and_active(email, encrypt_password(password), true)
end