Merged r9349 from trunk.

git-svn-id: svn+ssh://rubyforge.org/var/svn/redmine/branches/1.4-stable@9354 e93f8b46-1217-0410-a6f0-8f06a7374b81

app/controllers/issues_controller.rb

@@ -420,7 +420,16 @@ private
   def parse_params_for_bulk_issue_attributes(params)
     attributes = (params[:issue] || {}).reject {|k,v| v.blank?}
     attributes.keys.each {|k| attributes[k] = '' if attributes[k] == 'none'}
-    attributes[:custom_field_values].reject! {|k,v| v.blank?} if attributes[:custom_field_values]
+    if custom = attributes[:custom_field_values]
+      custom.reject! {|k,v| v.blank?}
+      custom.keys.each do |k|
+        if custom[k].is_a?(Array)
+          custom[k] << '' if custom[k].delete('__none__')
+        else
+          custom[k] = '' if custom[k] == '__none__'
+        end
+      end
+    end
     attributes
   end
 end

app/helpers/custom_fields_helper.rb

@@ -100,6 +100,7 @@ module CustomFieldsHelper
       when "list"
         options = []
         options << [l(:label_no_change_option), ''] unless custom_field.multiple?
+        options << [l(:label_none), '__none__'] unless custom_field.is_required?
         options += custom_field.possible_values_options(projects)
         select_tag(field_name, options_for_select(options),
           :id => field_id, :multiple => custom_field.multiple?)