diff --git a/app/helpers/application_helper.rb b/app/helpers/application_helper.rb
index f152e21..8586483 100644
--- a/app/helpers/application_helper.rb
+++ b/app/helpers/application_helper.rb
@@ -422,7 +422,8 @@ module ApplicationHelper
   end
 
   def html_hours(text)
-    text.gsub(%r{(\d+)\.(\d+)}, '<span class="hours hours-int">\1</span><span class="hours hours-dec">.\2</span>').html_safe
+    hours_int_sep_dec = Regexp.new("(\\d+)([\\.#{Regexp.escape l(:general_csv_decimal_separator)}])(\\d+)")
+    text.gsub(hours_int_sep_dec, '<span class="hours hours-int">\1</span><span class="hours hours-dec">\2\3</span>').html_safe
   end
 
   def authoring(created, author, options={})
diff --git a/app/helpers/queries_helper.rb b/app/helpers/queries_helper.rb
index 9ad2540..7a81a2c 100644
--- a/app/helpers/queries_helper.rb
+++ b/app/helpers/queries_helper.rb
@@ -150,6 +150,8 @@ module QueriesHelper
       content_tag('span',
         value.to_s(issue) {|other| link_to_issue(other, :subject => false, :tracker => false)}.html_safe,
         :class => value.css_classes_for(issue))
+    when :hours, :total_spent_hours, :estimated_hours
+      l_number("%.2f", value)
     else
       format_object(value)
     end
@@ -168,7 +170,7 @@ module QueriesHelper
     format_object(value, false) do |value|
       case value.class.name
       when 'Float'
-        sprintf("%.2f", value).gsub('.', l(:general_csv_decimal_separator))
+        l_number("%.2f", value)
       when 'IssueRelation'
         value.to_s(object)
       when 'Issue'
diff --git a/app/views/my/blocks/_timelog.html.erb b/app/views/my/blocks/_timelog.html.erb
index 747039c..99eda59 100644
--- a/app/views/my/blocks/_timelog.html.erb
+++ b/app/views/my/blocks/_timelog.html.erb
@@ -14,7 +14,7 @@ entries_by_day = entries.group_by(&:spent_on)
 <% end %>
 
 <div class="total-hours">
-<p><%= l(:label_total_time) %>: <%= html_hours("%.2f" % entries.sum(&:hours).to_f) %></p>
+<p><%= l(:label_total_time) %>: <%= html_hours(l_number("%.2f", entries.sum(&:hours).to_f)) %></p>
 </div>
 
 <% if entries.any? %>
@@ -31,7 +31,7 @@ entries_by_day = entries.group_by(&:spent_on)
     <tr class="odd">
     <td><strong><%= day == Date.today ? l(:label_today).titleize : format_date(day) %></strong></td>
     <td colspan="2"></td>
-    <td class="hours"><em><%= html_hours("%.2f" % entries_by_day[day].sum(&:hours).to_f) %></em></td>
+    <td class="hours"><em><%= html_hours(l_number("%.2f", entries_by_day[day].sum(&:hours).to_f)) %></em></td>
     <td></td>
     </tr>
     <% entries_by_day[day].each do |entry| -%>
@@ -39,7 +39,7 @@ entries_by_day = entries.group_by(&:spent_on)
     <td class="activity"><%= entry.activity %></td>
     <td class="subject"><%= entry.project %> <%= h(' - ') + link_to_issue(entry.issue, :truncate => 50) if entry.issue %></td>
     <td class="comments"><%= entry.comments %></td>
-    <td class="hours"><%= html_hours("%.2f" % entry.hours) %></td>
+    <td class="hours"><%= html_hours(l_number("%.2f", entry.hours)) %></td>
     <td class="buttons">
     <% if entry.editable_by?(@user) -%>
         <%= link_to image_tag('edit.png'), {:controller => 'timelog', :action => 'edit', :id => entry},
diff --git a/app/views/timelog/_report_criteria.html.erb b/app/views/timelog/_report_criteria.html.erb
index c86b219..5931e9e 100644
--- a/app/views/timelog/_report_criteria.html.erb
+++ b/app/views/timelog/_report_criteria.html.erb
@@ -8,9 +8,9 @@
   <% total = 0 -%>
   <% @report.periods.each do |period| -%>
     <% sum = sum_hours(select_hours(hours_for_value, @report.columns, period.to_s)); total += sum -%>
-    <td class="hours"><%= html_hours("%.2f" % sum) if sum > 0 %></td>
+    <td class="hours"><%= html_hours(l_number("%.2f", sum)) if sum > 0 %></td>
   <% end -%>
-  <td class="hours"><%= html_hours("%.2f" % total) if total > 0 %></td>
+  <td class="hours"><%= html_hours(l_number("%.2f", total)) if total > 0 %></td>
 </tr>
 <% if criterias.length > level+1 -%>
   <%= render(:partial => 'report_criteria', :locals => {:criterias => criterias, :hours => hours_for_value, :level => (level + 1)}) %>
diff --git a/app/views/timelog/report.html.erb b/app/views/timelog/report.html.erb
index 176f128..91c69a5 100644
--- a/app/views/timelog/report.html.erb
+++ b/app/views/timelog/report.html.erb
@@ -56,9 +56,9 @@
   <% total = 0 -%>
   <% @report.periods.each do |period| -%>
     <% sum = sum_hours(select_hours(@report.hours, @report.columns, period.to_s)); total += sum -%>
-    <td class="hours"><%= html_hours("%.2f" % sum) if sum > 0 %></td>
+    <td class="hours"><%= html_hours(l_number("%.2f", sum)) if sum > 0 %></td>
   <% end -%>
-  <td class="hours"><%= html_hours("%.2f" % total) if total > 0 %></td>
+  <td class="hours"><%= html_hours(l_number("%.2f", total)) if total > 0 %></td>
   </tr>
 </tbody>
 </table>
diff --git a/lib/redmine/i18n.rb b/lib/redmine/i18n.rb
index 9523f23..b429133 100644
--- a/lib/redmine/i18n.rb
+++ b/lib/redmine/i18n.rb
@@ -45,7 +45,12 @@ module Redmine
 
     def l_hours(hours)
       hours = hours.to_f
-      l((hours < 2.0 ? :label_f_hour : :label_f_hour_plural), :value => ("%.2f" % hours.to_f))
+      l((hours < 2.0 ? :label_f_hour : :label_f_hour_plural), :value => l_number("%.2f", hours.to_f))
+    end
+
+    def l_number(format, value)
+      return '' if value.blank?
+      sprintf(format, value).gsub('.', l(:general_csv_decimal_separator))
     end
 
     def l_hours_short(hours)