For example I've modified mod_mail.py in the following way: --- /dev/fd/63 2008-09-10 02:51:25.899925031 +0400 +++ /usr/lib/portage/pym/elog_modules/mod_mail.py 2008-09-10 02:50:46.000000000 +0400 @@ -19,6 +19,8 @@ mysubject = mysubject.replace("${HOST}", socket.getfqdn()) mymessage = portage_mail.create_message(myfrom, myrecipient, mysubject, fulltext) + mymessage['X-Generator'] = 'portage/elog' + mymessage['X-ELog-cpv'] = cpv try: portage_mail.send_mail(mysettings, mymessage) except PortageException, e: Reproducible: Always Steps to Reproduce: 1. Add mail to your PORTAGE_ELOG_SYSTEM 2. EBuild any package 3. Attempt to filter message not by subject Actual Results: Subject is bad field for filtering because it can be configured to match user language. Expected Results: Some technical field should be added for easy filtering.