Index: models/issue_query.rb
===================================================================
--- models/issue_query.rb	(revision 11998)
+++ models/issue_query.rb	(working copy)
@@ -232,6 +232,14 @@
     raise StatementInvalid.new(e.message)
   end
 
+  # Returns sum of all the issue's estimated_hours 
+  def issue_sum
+    Issue.sum(:estimated_hours, :include => [:status, :project],
+    :conditions => statement << " AND #{Issue.table_name}.rgt - #{Issue.table_name}.lft = 1")
+  rescue ::ActiveRecord::StatementInvalid => e
+    raise StatementInvalid.new(e.message)  
+  end
+
   # Returns the issue count by group or nil if query is not grouped
   def issue_count_by_group
     r = nil
@@ -252,6 +260,27 @@
     raise StatementInvalid.new(e.message)
   end
 
+  # Returns  sum of the issue's estimated_hours by group or nil if query is not grouped
+  def issue_sum_by_group
+    r = nil
+    if grouped?
+      begin
+        r = Issue.sum(:estimated_hours, :group => group_by_statement, :include => [:status, :project], 
+        :conditions => statement << " AND #{Issue.table_name}.rgt - #{Issue.table_name}.lft = 1")
+      rescue ActiveRecord::RecordNotFound
+        r= {r => issue_sum}
+      end
+      
+      c = group_by_column
+      if c.is_a?(QueryCustomFieldColumn)
+        r = r.keys.inject({}) {|h, k| h[c.custom_field.cast_value(k)] = r[k]; h}
+      end
+    end
+    r
+  rescue ::ActiveRecord::StatementInvalid => e
+    raise StatementInvalid.new(e.message)
+  end
+
   # Returns the issues
   # Valid options are :order, :offset, :limit, :include, :conditions
   def issues(options={})
Index: controllers/issues_controller.rb
===================================================================
--- controllers/issues_controller.rb	(revision 11998)
+++ controllers/issues_controller.rb	(working copy)
@@ -78,6 +78,7 @@
                               :offset => @offset,
                               :limit => @limit)
       @issue_count_by_group = @query.issue_count_by_group
+      @issue_sum_by_group = @query.issue_sum_by_group
 
       respond_to do |format|
         format.html { render :template => 'issues/index', :layout => !request.xhr? }
Index: views/issues/_list.html.erb
===================================================================
--- views/issues/_list.html.erb	(revision 11998)
+++ views/issues/_list.html.erb	(working copy)
@@ -22,7 +22,7 @@
     <tr class="group open">
       <td colspan="<%= query.inline_columns.size + 2 %>">
         <span class="expander" onclick="toggleRowGroup(this);">&nbsp;</span>
-        <%= group.blank? ? l(:label_none) : column_content(@query.group_by_column, issue) %> <span class="count"><%= @issue_count_by_group[group] %></span>
+        <%= group.blank? ? l(:label_none) : column_content(@query.group_by_column, issue) %> <span class="count"><%= @issue_count_by_group[group] %> (<%= l(:field_estimated_hours) %>: <%= l(:label_f_hour_plural, :value => @issue_sum_by_group[group]) %>)</span>
         <%= link_to_function("#{l(:button_collapse_all)}/#{l(:button_expand_all)}",
                              "toggleAllRowGroups(this)", :class => 'toggle-all') %>
       </td>
@@ -45,3 +45,7 @@
 </table>
 </div>
 <% end -%>
+<p align="right"
+    current page: <b><%=issues.reject{|issue| issue.children?}.collect(&:estimated_hours).reject {|hours| hours.nil?}.sum %></b>
+    <%= l(:field_estimated_hours) %>: <b><%= l(:label_f_hour_plural, :value => @query.issue_sum) %></b>
+</p>