--- app/models/mail_handler.rb	2014-03-29 17:56:13.000000000 +0100
+++ app/models/mail_handler.new.rb	2014-06-16 08:27:02.067372711 +0200
@@ -275,6 +275,18 @@
                           :content_type => attachment.mime_type)
       end
     end
+    if (parts = email.all_parts.select {|p| p.mime_type == 'text/html'}).present?
+      html_parts = parts.map do |p|
+        body_charset = p.charset.respond_to?(:force_encoding) ?
+                        Mail::RubyVer.pick_encoding(p.charset).to_s : p.charset
+        Redmine::CodesetUtil.to_utf8(p.body.decoded, body_charset)
+      end.join("</hr>")
+      obj.attachments << Attachment.create(:container => obj,
+                          :file => html_parts,
+                          :filename => 'HTML version',
+                          :author => user,
+                          :content_type => 'text/html')
+    end
   end
 
   # Returns false if the +attachment+ of the incoming email should be ignored