Redmine Internal Error

[clikonco]

After installation/setup of plugin, I run into Internal error. Below is error taken from log.

<ActionView::Template::Error (can't convert Symbol into Integer):
    11: <%= stylesheet_link_tag 'rtl', :media => 'all' if l(:direction) == 'rtl' %>
    12: <%= javascript_heads %>
    13: <%= heads_for_theme %>
    14: <%= call_hook :view_layouts_base_html_head %>
    15: <!-- page specific tags -->
    16: <%= yield :header_tags -%>
    17: </head>
  lib/redmine/hook.rb:61:in `block (2 levels) in call_hook'
  lib/redmine/hook.rb:61:in `each'
  lib/redmine/hook.rb:61:in `block in call_hook'
  lib/redmine/hook.rb:58:in `tap'
  lib/redmine/hook.rb:58:in `call_hook'
  lib/redmine/hook.rb:158:in `call_hook'
  app/views/layouts/base.html.erb:14:in `_app_views_layouts_base_html_erb___398893353_47506764'
  app/views/layouts/admin.html.erb:8:in `_app_views_layouts_admin_html_erb___638762702_49400064'
  app/controllers/settings_controller.rb:28:in `index'>

ENV:

Environment:
  Redmine version             2.5.1.stable
  Ruby version                   1.9.3-p231 (2012-05-25) [i386-mingw32]
  Rails version                    3.2.17
  Environment                    production
  Database adapter            Mysql2