ActionView::Template::Error (undefined method `is_closed?' for nil:NilClass):
    6: <h3><%= format_activity_day(day) %></h3>
    7: <dl>
    8: <% sort_activity_events(@events_by_day[day]).each do |e, in_group| -%>
    9:   <dt class="<%= e.event_type %> <%= "grouped" if in_group %> <%= User.current.logged? && e.respond_to?(:event_author) && User.current == e.event_author ? 'me' : nil %>">
    10:   <%= avatar(e.event_author, :size => "24") if e.respond_to?(:event_author) %>
    11:   <span class="time"><%= format_time(e.event_datetime, false) %></span>
    12:   <%= content_tag('span', h(e.project), :class => 'project') if @project.nil? || @project != e.project %>
  app/models/issue.rb:677:in `closed?'
  app/models/issue.rb:57:in `block in <class:Issue>'