Redmine

Hello,
I was upgraded redmine to the latest version.
When i try to go to /settings page, its gives 500 internal error and in the logs says;

 Rendered settings/_general.html.erb (220.2ms)
  Rendered settings/_display.html.erb (1488.5ms)
  Rendered settings/_authentication.html.erb (15.8ms)
  Rendered common/_tabs.html.erb (1749.7ms)
  Rendered settings/edit.html.erb within layouts/admin (1780.5ms)
Completed 500 Internal Server Error in 1862ms (ActiveRecord: 12.9ms)

ActionView::Template::Error (undefined method `password_max_age' for #<Class:0x00000004f5f9c0>):
    15: <p><%= setting_text_field :password_min_length, :size => 6 %></p>
    16:
    17: <p>
    18:   <%= setting_select :password_max_age, [[l(:label_disabled), 0]] + [7, 30, 60, 90, 180, 365].collect{|days| [l('datetime.distance_in_words.x_days', :count => days), days.to_s]} %>
    19: </p>
    20:
    21: <p><%= setting_check_box :lost_password, :label => :label_password_lost %></p>
  app/helpers/settings_helper.rb:39:in `setting_select'
  app/views/settings/_authentication.html.erb:18:in `block in _app_views_settings__authentication_html_erb__2528163363059503313_25186860'
  app/views/settings/_authentication.html.erb:1:in `_app_views_settings__authentication_html_erb__2528163363059503313_25186860'
  app/views/common/_tabs.html.erb:22:in `block in _app_views_common__tabs_html_erb___160014599560785040_69827415326320'
  app/views/common/_tabs.html.erb:21:in `each'
  app/views/common/_tabs.html.erb:21:in `_app_views_common__tabs_html_erb___160014599560785040_69827415326320'
  app/helpers/application_helper.rb:321:in `render_tabs'
  app/views/settings/edit.html.erb:3:in `_app_views_settings_edit_html_erb___243887154580296522_69827414187380'
  app/controllers/settings_controller.rb:28:in `index'

How can i fix this problem ?
Thanks...