diff --git a/lib/redmine/utils.rb b/lib/redmine/utils.rb
index d255dfa916..fb487a7996 100644
--- a/lib/redmine/utils.rb
+++ b/lib/redmine/utils.rb
@@ -106,22 +106,10 @@ module Redmine
 
       # Adds working days to the given date
       def add_working_days(date, working_days)
-        if working_days > 0
-          weeks = working_days / (7 - non_working_week_days.size)
-          result = weeks * 7
-          days_left = working_days - weeks * (7 - non_working_week_days.size)
-          cwday = date.cwday
-          while days_left > 0
-            cwday += 1
-            unless non_working_week_days.include?(((cwday - 1) % 7) + 1)
-              days_left -= 1
-            end
-            result += 1
-          end
-          next_working_date(date + result)
-        else
-          date
+        working_days.times do
+          date = next_working_date(date + 1)
         end
+        date
       end
 
       # Returns the date of the first day on or after the given date that is a working day
diff --git a/test/unit/lib/redmine/utils/date_calculation.rb b/test/unit/lib/redmine/utils/date_calculation.rb
index 4228486787..80076df56d 100644
--- a/test/unit/lib/redmine/utils/date_calculation.rb
+++ b/test/unit/lib/redmine/utils/date_calculation.rb
@@ -63,6 +63,8 @@ class Redmine::Utils::DateCalculationTest < ActiveSupport::TestCase
       assert_add_working_days '2012-10-31', '2012-10-10', 15
       assert_add_working_days '2012-10-19', '2012-10-09', 8
       assert_add_working_days '2012-10-23', '2012-10-11', 8
+      assert_add_working_days '2012-10-26', '2012-10-20', 5
+      assert_add_working_days '2012-10-26', '2012-10-21', 5
     end
   end