diff --git a/app/controllers/graders_controller.rb b/app/controllers/graders_controller.rb
--- a/app/controllers/graders_controller.rb
+++ b/app/controllers/graders_controller.rb
@@ -80,6 +80,7 @@
       when "ruby"   then Rouge::Lexers::Ruby.new
       when "python" then Rouge::Lexers::Python.new
       when "java"   then Rouge::Lexers::Java.new
+      when "php"    then Rouge::Lexers::PHP.new
     end
     @formatted_code = formatter.format(lexer.lex(@submission.source))
     @css_style = Rouge::Themes::ThankfulEyes.render(scope: '.highlight')
diff --git a/app/controllers/problems_controller.rb b/app/controllers/problems_controller.rb
--- a/app/controllers/problems_controller.rb
+++ b/app/controllers/problems_controller.rb
@@ -89,8 +89,30 @@
         render :action => 'edit' and return
       end
     end
+    if params[:file] and params[:file].content_type != 'application/pdf'
+        flash[:notice] = 'Error: Uploaded file is not PDF'
+        render :action => 'edit' and return
+    end
     if @problem.update_attributes(params[:problem])
       flash[:notice] = 'Problem was successfully updated.'
+      unless params[:file] == nil or params[:file] == ''
+        flash[:notice] = 'Problem was successfully updated and a new PDF file is uploaded.'
+        out_dirname = "#{Problem.download_file_basedir}/#{@problem.id}"
+        if not FileTest.exists? out_dirname
+          Dir.mkdir out_dirname
+        end
+
+        out_filename = "#{out_dirname}/#{@problem.name}.pdf"
+        if FileTest.exists? out_filename
+          File.delete out_filename
+        end
+
+        File.open(out_filename,"wb") do |file|
+          file.write(params[:file].read)
+        end
+        @problem.description_filename = "#{@problem.name}.pdf"
+        @problem.save
+      end
       redirect_to :action => 'show', :id => @problem
     else
       render :action => 'edit'
diff --git a/app/views/main/_submission.html.haml b/app/views/main/_submission.html.haml
--- a/app/views/main/_submission.html.haml
+++ b/app/views/main/_submission.html.haml
@@ -2,6 +2,8 @@
 %tr{:class => ((submission_counter%2==0) ? "info-even" : "info-odd")}
   %td.info{:align => "center"}
     = submission_counter+1
+  %td.info{:align => "center"}
+    = link_to "##{submission.id}", controller: :graders, action: :submission, id: submission.id
   %td.info= format_short_time(submission.submitted_at)
   %td.info{:align => "center"}
     = link_to('[load]',{:action => 'source', :id => submission.id})
diff --git a/app/views/main/submission.html.haml b/app/views/main/submission.html.haml
--- a/app/views/main/submission.html.haml
+++ b/app/views/main/submission.html.haml
@@ -13,6 +13,7 @@
   - if @submissions.length>0
     %table.info
       %tr.info-head
+        %th.info No.
         %th.info #
         %th.info At
         %th.info Source
diff --git a/app/views/problems/_form.html.erb b/app/views/problems/_form.html.erb
--- a/app/views/problems/_form.html.erb
+++ b/app/views/problems/_form.html.erb
@@ -48,5 +48,7 @@
 <p><label for="problem_url">URL</label><br/>
 <%= text_field 'problem', 'url'  %></p>
 
+<p>Task PDF <%= file_field_tag 'file' %></p>
+
 
 <!--[eoform:problem]-->
diff --git a/app/views/problems/edit.html.erb b/app/views/problems/edit.html.erb
--- a/app/views/problems/edit.html.erb
+++ b/app/views/problems/edit.html.erb
@@ -1,6 +1,6 @@
 <h1>Editing problem</h1>
 
-<%= form_tag :action => 'update', :id => @problem do %>
+<%= form_tag({action: 'update', id: @problem},multipart: true) do %>
   <%= render :partial => 'form' %>
   <%= submit_tag 'Edit' %>
 <% end %>
diff --git a/app/views/user_admin/list.html.erb b/app/views/user_admin/list.html.erb
--- a/app/views/user_admin/list.html.erb
+++ b/app/views/user_admin/list.html.erb
@@ -68,8 +68,9 @@
   
 <% for user in @users %>
   <tr class="info-<%= cycle("odd","even") %>">
+    <td><%= link_to user.login, controller: :users, :action => 'profile', :id => user %></td>
     <% for column in User.content_columns %>
-      <% if !@hidden_columns.index(column.name) %>
+      <% if !@hidden_columns.index(column.name) and column.name != 'login' %>
         <td><%=h user.send(column.name) %></td>
       <% end %>
     <% end %>
diff --git a/app/views/users/profile.html.haml b/app/views/users/profile.html.haml
--- a/app/views/users/profile.html.haml
+++ b/app/views/users/profile.html.haml
@@ -3,7 +3,7 @@
 
 %script{:type=>"text/javascript"}
   $(function () {
-  $('#submission_table').tablesorter({widgets: ['zebra','filter']});
+  $('#submission_table').tablesorter({widgets: ['zebra']});
   });
 
 :css
@@ -27,8 +27,9 @@
     %tr
       %th ID
       %th Problem code
-      %th Problem name
+      %th Problem full name
       %th Language
+      %th Submitted at
       %th Result
       %th Score
       - if session[:admin]
@@ -41,6 +42,7 @@
         %td= s.problem.name
         %td= s.problem.full_name
         %td= s.language.pretty_name
+        %td  #{s.submitted_at.strftime('%Y-%m-%d %H:%M')} (#{time_ago_in_words(s.submitted_at)} ago)
         %td.fix-width= s.grader_comment
         %td= (s.points*100)/s.problem.full_score
         - if session[:admin]