Redmine

Environment:
Redmine version 2.6.1.stable
Ruby version 2.0.0-p594 (2014-10-27) [i386-mingw32]
Rails version 3.2.21
Environment production
Database adapter SQLServer
SCM:
Subversion 1.8.10
Git 1.9.5
Filesystem
Redmine plugins:
no plugin installed

issue click after error..

Started GET "/redmine/issues/90" for 127.0.0.1 at 2015-02-23 18:07:03 +0900
Processing by IssuesController#show as HTML
Parameters: {"id"=>"90"}
Current user: 11059 (id=5)
Rendered issues/_action_menu.html.erb (16.0ms)
Rendered issue_relations/_form.html.erb (4.0ms)
Rendered issues/_relations.html.erb (8.0ms)
Rendered issues/_history.html.erb (5.0ms)
Rendered issues/show.html.erb within layouts/base (108.0ms)
Completed 500 Internal Server Error in 439.0ms

ActionView::Template::Error (undefined method `div' for nil:NilClass):
9:
10: <% if journal.details.any? >
11: <ul class="details">
12: < details_to_strings(journal.visible_details).each do |string| >
13: <li><= string ></li>
14: < end %>
15: </ul>
app/helpers/issues_helper.rb:306:in `show_detail'
app/helpers/issues_helper.rb:277:in `block in details_to_strings'
app/helpers/issues_helper.rb:263:in `each'
app/helpers/issues_helper.rb:263:in `details_to_strings'
app/views/issues/_history.html.erb:12:in `block in app_views_issues_history_html_erb__777544118_64277424'
app/views/issues/_history.html.erb:2:in `each'
app/views/issues/_history.html.erb:2:in `_app_views_issues__history_html_erb__777544118_64277424'
app/views/issues/show.html.erb:120:in `_app_views_issues_show_html_erb__472113127_60261312'
app/controllers/issues_controller.rb:128:in `block (2 levels) in show'
app/controllers/issues_controller.rb:125:in `show'