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Path: gf5ni2985800qab.0!nntp.google.com!e17no11934558qar.0!postnews.google.com!glegroupsg2000goo.googlegroups.com!not-for-mail
Newsgroups: list.postfix.users
Date: Mon, 29 Oct 2012 08:24:42 -0700 (PDT)
Complaints-To: groups-abuse@google.com
Injection-Info: glegroupsg2000goo.googlegroups.com; posting-host=88.49.250.55; posting-account=91zXrQoAAAACpyy2dsPio9V1ArP434uO
NNTP-Posting-Host: 88.49.250.55
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Message-ID: <bcd29e85-88fa-4c46-a634-3dba5fc35427@googlegroups.com>
Subject: mail from google groups
From: gianni.pape...@gmail.com
Injection-Date: Mon, 29 Oct 2012 15:24:42 +0000
Content-Type: text/plain; charset=ISO-8859-1

Hi all;
i manage a postfix MTA for my company, and when we recive mail from a google group i always see this sendere in postfix logs:

from=<tf+bncCK-qtq6JFxCo1Nr_BBoES2fpCA@sender_domain.com> to=<u...@mydomain.com>

Can anyone explain me what the hell tf+bncCK-qtq6JFxCo1Nr_BBoES2fpCA is?

Users see tf+bncCK-qtq6JFxCo1Nr_BBoES2fpCA as mail sender in their client; is it normal?

thanks.