Index: trunk/lib/redmine/wiki_formatting/macros.rb
===================================================================
--- trunk/lib/redmine/wiki_formatting/macros.rb	(revision 13171)
+++ trunk/lib/redmine/wiki_formatting/macros.rb	(working copy)
@@ -236,8 +236,8 @@
         size = nil unless size > 0
         if obj && obj.respond_to?(:attachments) && attachment = Attachment.latest_attach(obj.attachments, filename)
           title = options[:title] || attachment.title
-          img = image_tag(url_for(:controller => 'attachments', :action => 'thumbnail', :id => attachment, :size => size), :alt => attachment.filename)
-          link_to(img, url_for(:controller => 'attachments', :action => 'show', :id => attachment), :class => 'thumbnail', :title => title)
+          img = image_tag(url_for(:only_path => false, :controller => 'attachments', :action => 'thumbnail', :id => attachment, :size => size), :alt => attachment.filename)
+          link_to(img, url_for(:only_path => false, :controller => 'attachments', :action => 'show', :id => attachment), :class => 'thumbnail', :title => title)
         else
           raise "Attachment #{filename} not found"
         end