diff --git a/app/models/thumbnail.rb b/app/models/thumbnail.rb
index 215c2e0..413b0f1 100644
--- a/app/models/thumbnail.rb
+++ b/app/models/thumbnail.rb
@@ -1,4 +1,9 @@
 class Thumbnail < ActiveRecord::Base
+
+  attr_accessible :uploaded_data
+  # mass assigned by attachment_fu
+  attr_accessible :content_type, :filename, :thumbnail_resize_options, :thumbnail, :parent_id
+
   has_attachment :storage => :file_system,
     :content_type => :image, :max_size => 5.megabytes, processor: 'Rmagick'
   validates_as_attachment
@@ -7,5 +12,4 @@ class Thumbnail < ActiveRecord::Base
 
   postgresql_attachment_fu
 
-  attr_accessible :uploaded_data
 end
diff --git a/test/factories.rb b/test/factories.rb
index 1a1e4c1..2970f1d 100644
--- a/test/factories.rb
+++ b/test/factories.rb
@@ -31,7 +31,8 @@ module Noosfero::Factory
     if respond_to?(target)
       send(target, attrs)
     else
-      obj = build(name, attrs)
+      obj = build name
+      attrs.each{ |a, v| obj.send "#{a}=", v }
       obj.save!
       obj
     end
diff --git a/test/test_helper.rb b/test/test_helper.rb
index 3562a60..b13a823 100644
--- a/test/test_helper.rb
+++ b/test/test_helper.rb
@@ -138,6 +138,7 @@ class ActiveSupport::TestCase
   def find_tag_in_string text, options
     doc = Nokogiri::HTML.fragment text
     tag = doc.css(options[:tag]).first
+    return unless tag
     content = tag.text.strip
 
     attributes = {}; tag.attributes.each do |a, v|
@@ -146,7 +147,7 @@ class ActiveSupport::TestCase
       attributes[a] = v.value
     end
 
-    ret = tag.present?
+    ret = true
     ret &&= options[:attributes].blank? || attributes == options[:attributes]
     ret &&= options[:content].blank? || content == options[:content]
     ret
diff --git a/test/unit/uploaded_file_test.rb b/test/unit/uploaded_file_test.rb
index 8a5acfe..1bd58c6 100644
--- a/test/unit/uploaded_file_test.rb
+++ b/test/unit/uploaded_file_test.rb
@@ -347,13 +347,13 @@ class UploadedFileTest < ActiveSupport::TestCase
     'INVALID' => 5.megabytes,   # use default for invalid input
     '1ZYX'    => 5.megabytes,   # use default for invalid input
   }.each do |input,output|
-    test 'maximum upload size: convert %s into %s' % [input, output] do
+    should 'maximum upload size: convert %s into %s' % [input, output] do
       NOOSFERO_CONF.expects(:[]).with('max_upload_size').returns(input)
       assert_equal output, UploadedFile.max_size
     end
   end
-  test 'max_size should always return an integer' do
-    NOOSFERO_CONF.expects(:[]).with('max_upload_size').returns("0.5 GB")
+  should 'max_size should always return an integer' do
+    NOOSFERO_CONF.expects(:[]).with('max_upload_size').returns("0.5 GB").at_least_once
     assert_instance_of Fixnum, UploadedFile.max_size
   end
 
--
libgit2 0.21.2