diff --git a/app/helpers/content_viewer_helper.rb b/app/helpers/content_viewer_helper.rb
index f7945d1..1cc3afa 100644
--- a/app/helpers/content_viewer_helper.rb
+++ b/app/helpers/content_viewer_helper.rb
@@ -60,4 +60,12 @@ module ContentViewerHelper
     }
   end
 
+  def addthis_image_tag
+    if File.exists?(File.join(Rails.root, 'public', theme_path, 'images', 'addthis.gif'))
+      image_tag(File.join(theme_path, 'images', 'addthis.gif'), :border => 0, :alt => '')
+    else
+      image_tag("/images/bt-bookmark.gif", :width => 53, :height => 16, :border => 0, :alt => '')
+    end
+  end
+
 end
diff --git a/app/views/content_viewer/view_page.rhtml b/app/views/content_viewer/view_page.rhtml
index 7fb307b..2539796 100644
--- a/app/views/content_viewer/view_page.rhtml
+++ b/app/views/content_viewer/view_page.rhtml
@@ -47,7 +47,8 @@
   };
   addthis_options = '<%= escape_javascript( NOOSFERO_CONF['addthis_options'] ) %>';
 </script>
-<a href="http://www.addthis.com/bookmark.php" id="bt_addThis" target="_blank" onmouseover="return addthis_open(this, '', '[URL]')" onmouseout="addthis_close()" onclick="return addthis_sendto()"><img src="/images/bt-bookmark.gif" width="53" height="16" border="0" alt="" /></a><script type="text/javascript" src="http://s7.addthis.com/js/152/addthis_widget.js"></script>
+<a href="http://www.addthis.com/bookmark.php" id="bt_addThis" target="_blank" onmouseover="return addthis_open(this, '', '[URL]')" onmouseout="addthis_close()" onclick="return addthis_sendto()"><%= addthis_image_tag %></a>
+<script type="text/javascript" src="http://s7.addthis.com/js/152/addthis_widget.js"></script>
 </div>
 <% end %>
 
diff --git a/test/unit/content_viewer_helper_test.rb b/test/unit/content_viewer_helper_test.rb
index 84b1eb6..aeff4cc 100644
--- a/test/unit/content_viewer_helper_test.rb
+++ b/test/unit/content_viewer_helper_test.rb
@@ -115,6 +115,20 @@ class ContentViewerHelperTest < Test::Unit::TestCase
     assert_equal "http://www.facebook.com/sharer.php?s=100&p[title]=Some+title&p[summary]=This+is+a+test&p[url]=http%3A%2F%2Fnoosfero.org%2Fblog_helper_test%2Fsome-title&p[images][0]=http%3A%2F%2Fnoosfero.org%2Fimages%2Fx.png", addthis_facebook_url(a)
   end
 
+  should 'theme provides addthis custom icon' do
+    stubs(:session).returns({:theme => 'base'})
+    File.expects(:exists?).with(anything).returns(true)
+    Environment.any_instance.stubs(:default_hostname).returns('noosfero.org')
+    assert_match 'addthis.gif', addthis_image_tag
+  end
+
+  should 'use default addthis icon if theme has no addthis.gif image' do
+    stubs(:session).returns({:theme => 'base'})
+    File.expects(:exists?).with(anything).returns(false)
+    Environment.any_instance.stubs(:default_hostname).returns('noosfero.org')
+    assert_match 'bt-bookmark.gif', addthis_image_tag
+  end
+
   protected
 
   include ActionView::Helpers::TextHelper
@@ -138,3 +152,6 @@ end
 def url_for(args = {})
   ['http:/', args[:host], args[:profile], args[:page]].join('/')
 end
+def image_tag(file, args = {})
+  file
+end
--
libgit2 0.21.2