diff --git a/app/helpers/repositories_helper.rb b/app/helpers/repositories_helper.rb
index 074dfa4..f19d993 100644
--- a/app/helpers/repositories_helper.rb
+++ b/app/helpers/repositories_helper.rb
@@ -117,6 +117,7 @@ module RepositoriesHelper
   end
   
   def to_utf8(str)
+    return str if str.blank?
     if str.respond_to?(:force_encoding)
       str.force_encoding('UTF-8')
     else
diff --git a/app/models/changeset.rb b/app/models/changeset.rb
index 0a60813..5e1ee19 100644
--- a/app/models/changeset.rb
+++ b/app/models/changeset.rb
@@ -247,6 +247,7 @@ class Changeset < ActiveRecord::Base
   end
 
   def self.to_utf8(str)
+    return str if str.blank?
     encoding = Setting.commit_logs_encoding.to_s.strip
     unless encoding.blank? || encoding == 'UTF-8'
       begin