gistfile1.rb

        calendar({:year => Date.today.year, :month => Date.today.month, :first_day_of_week => 1}) do |d|
          cell_text = "#{d.mday}<br />" 
          cell_attrs = {:class => 'day'}
          @incompleted_tasks.each do |task|
            if task.deadline == d
              cell_text << link_to(task.name, project_task_path(@project.id, task.id)) << "<br />"
              if task.deadline < Date.today
                cell_attrs[:class] = 'specialDayLated'
              else
                cell_attrs[:class] = 'specialDay'
              end
            end
          end
          [cell_text, cell_attrs]
        end