wrong number of arguments (0 for 1) ArgumentError in XXXXController#create

[Peter Moh]

I get wrong number of arguments (0 for 1) error.
The create action works with regular validates but authenticate/salt processing.

Please point out what does the message mean?

The create action works fine without calling and authenticate(us er_id, password).

require 'digest/sha1'

class Ctkuser < ActiveRecord::Base

validates_presence_of :user_id
validates_uniqueness_of :user_id
 
 
 attr_accessor :password_confirmation
 validates_confirmation_of :password
    
    
 validate :password_non_blank
  
#'passwrod' is a virtal attribute? 
 def password
      @password
 end
def password_non_blank
     errors.add(:password, "Missing password") if hashed_password.blank?
end
end

But if put following code to model/ctkuser.rb, the error happens:

def self.authenticate(user_id, password)
      ctkuser = self.find_by_user_id(user_id)
      if ctkuser
             expected_password = encrypted_password(password, ctkuser.salt)
             if ctkuser.hashed_password != expected_password 
                ctkuser = nil
             end
       end
       ctkuser 
  end      

 #'passwrod' is a virtal attribute?
 def password
    @password
 end
 
 def password(pwd)
     @password = pwd
     return if pwd.blank?
     create_new_salt
     self.hashed_password = Ctkuser.encrpyted_password(self.password, self.salt)
 end
 
 private
 
 def password_non_blank
     errors.add(:password, "Missing password") if hashed_password.blank?
 end
 
 def create_new_salt
     self.salt = self.object_id.to_s + rand.to_s
 end
 
 def self.encrypted_password(password, salt)
     string_to_hash = password + "wibble" + salt
     Digest::SHA1.hexdigest(string_to_hash) 
 end

ArgumentError in CtkusersController#create 
wrong number of arguments (0 for 1)

Request
Parameters: 

{"commit"=>"Add User",
 "authenticity_token"=>"Yylcw4I9jalsAPL3sCNL8rmcAOr4GhaZiQ42fCv4IK4=",
 "ctkuser"=>{"is_locked"=>"NO",
 "user_role"=>"1",
 "added_by"=>"SESSION-USER",
 "hashed_password"=>"e343",
 "updated_on"=>"2011-04-29",
 "user_id"=>"TEST04282011_No51",
 "updated_by"=>"SESSION-USER",
 "last_name"=>"Chrey",
 "agency_sequence"=>"2",
 "added_on"=>"2011-04-29",
 "is_change_password"=>"NO",
 "first_name"=>"Melissa",
 "email"=>"mCherey@mas.com"}}