Redmine

I used redmine 2.0.3 with ruby 1.9.3

when I have installed and start the server, there's an error when I open the configuration/setting page.

Started GET "/settings" for 127.0.0.1 at 2012-08-31 12:54:50 +0800
Processing by SettingsController#index as HTML
  Rendered settings/_general.html.erb (31.2ms)
  Rendered settings/_display.html.erb (78.1ms)
  Rendered settings/_authentication.html.erb (0.0ms)
  Rendered settings/_projects.html.erb (93.8ms)
  Rendered common/_tabs.html.erb (281.2ms)
  Rendered settings/edit.html.erb within layouts/admin (375.0ms)
Completed 500 Internal Server Error in 453ms

ActionView::Template::Error (incompatible character encodings: UTF-8 and ASCII-8
BIT):
    8:
    9: <p><%= setting_check_box :sequential_project_identifiers %></p>
    10:
    11: <p><%= setting_select :new_project_user_role_id,
    12:                       Role.find_all_givable.collect {|r| [r.name, r.id.t
o_s]},
    13:                       :blank => "--- #{l(:actionview_instancetag_blank_o
ption)} ---" %></p>
    14: </div>
  app/helpers/settings_helper.rb:39:in `setting_select'
  app/views/settings/_projects.html.erb:11:in `block in _app_views_settings__pro
jects_html_erb___820201913_33769716'
  app/views/settings/_projects.html.erb:1:in `_app_views_settings__projects_html
_erb___820201913_33769716'
  app/views/common/_tabs.html.erb:24:in `block in _app_views_common__tabs_html_e
rb__72855970_7909884'
  app/views/common/_tabs.html.erb:23:in `each'
  app/views/common/_tabs.html.erb:23:in `_app_views_common__tabs_html_erb__72855
970_7909884'
  app/helpers/application_helper.rb:231:in `render_tabs'
  app/views/settings/edit.html.erb:3:in `_app_views_settings_edit_html_erb___411
495535_39833808'
  app/controllers/settings_controller.rb:26:in `index'