diff --git a/app/helpers/application_helper.rb b/app/helpers/application_helper.rb
index 78e5bdc65..cc26127d6 100644
--- a/app/helpers/application_helper.rb
+++ b/app/helpers/application_helper.rb
@@ -95,7 +95,7 @@ module ApplicationHelper
     return nil unless time
     time = time.to_time if time.is_a?(String)
     zone = User.current.time_zone
-    local = zone ? time.in_time_zone(zone) : (time.utc? ? time.utc_to_local : time)
+    local = zone ? time.in_time_zone(zone) : (time.utc? ? time.localtime : time)
     @date_format ||= (Setting.date_format.blank? || Setting.date_format.size < 2 ? l(:general_fmt_date) : Setting.date_format)
     @time_format ||= (Setting.time_format.blank? ? l(:general_fmt_time) : Setting.time_format)
     include_date ? local.strftime("#{@date_format} #{@time_format}") : local.strftime(@time_format)
diff --git a/app/models/user.rb b/app/models/user.rb
index 4f82f61b2..132896ad9 100644
--- a/app/models/user.rb
+++ b/app/models/user.rb
@@ -144,7 +144,7 @@ class User < ActiveRecord::Base
   end
   
   def time_zone
-    self.pref.time_zone.nil? ? nil : TimeZone[self.pref.time_zone]
+    @time_zone ||= (self.pref.time_zone.blank? ? nil : TimeZone[self.pref.time_zone])
   end
   
   def wants_comments_in_reverse_order?
diff --git a/test/unit/helpers/application_helper_test.rb b/test/unit/helpers/application_helper_test.rb
index 452c0b535..6db029ada 100644
--- a/test/unit/helpers/application_helper_test.rb
+++ b/test/unit/helpers/application_helper_test.rb
@@ -351,4 +351,12 @@ EXPECTED
     assert_equal now.strftime('%d %m %Y %H %M'), format_time(now)
     assert_equal now.strftime('%H %M'), format_time(now, false)
   end
+  
+  def test_utc_time_format
+    now = Time.now.utc
+    Setting.date_format = '%d %m %Y'
+    Setting.time_format = '%H %M'
+    assert_equal Time.now.strftime('%d %m %Y %H %M'), format_time(now)
+    assert_equal Time.now.strftime('%H %M'), format_time(now, false)
+  end
 end