Index: app/models/custom_value.rb
===================================================================
--- app/models/custom_value.rb	(revision 4164)
+++ app/models/custom_value.rb	(working copy)
@@ -16,9 +16,13 @@
 # Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
 
 class CustomValue < ActiveRecord::Base
+  include Redmine::I18n
+  
   belongs_to :custom_field
   belongs_to :customized, :polymorphic => true
 
+  before_save :transform
+
   def after_initialize
     if new_record? && custom_field && (customized_type.blank? || (customized && customized.new_record?))
       self.value ||= custom_field.default_value
@@ -41,7 +45,7 @@
   def to_s
     value.to_s
   end
-  
+ 
 protected
   def validate
     if value.blank?
@@ -58,10 +62,17 @@
       when 'float'
         begin; Kernel.Float(value); rescue; errors.add(:value, :invalid) end
       when 'date'
-        errors.add(:value, :not_a_date) unless value =~ /^\d{4}-\d{2}-\d{2}$/
+        errors.add(:value, :not_a_date) unless parse_user_date(value)
       when 'list'
         errors.add(:value, :inclusion) unless custom_field.possible_values.include?(value)
       end
     end
   end
+
+private
+
+  def transform
+    self.value = parse_user_date(value) if custom_field.field_format == 'date'
+  end
+
 end
Index: lib/redmine/i18n.rb
===================================================================
--- lib/redmine/i18n.rb	(revision 4164)
+++ lib/redmine/i18n.rb	(working copy)
@@ -39,6 +39,20 @@
       return nil unless date
       Setting.date_format.blank? ? ::I18n.l(date.to_date) : date.strftime(Setting.date_format)
     end
+
+    def parse_user_date(datestring)
+      return nil unless datestring
+      begin
+        if datestring =~ /^\d{4}-\d{2}-\d{2}$/
+          r = Date.strptime(datestring, '%F')
+        elsif
+          r = Setting.date_format.blank? ? Date.parse(datestring) : Date.strptime(datestring, Setting.date_format)
+        end
+      rescue
+        r = nil
+      end
+      return r
+    end
     
     def format_time(time, include_date = true)
       return nil unless time