GMail Uses SPF >From the headers of a spam I received:

X-Gmail-Received: b241a60ed4458e9d1b055cb3c8c2ce6ea0e7bd81
Delivered-To: xxxxxx...@gmail.com
Received: by 10.38.72.72 with SMTP id u72cs10727rna;
Fri, 17 Sep 2004 04:30:58 -0700 (PDT)
Received: by 10.11.116.71 with SMTP id o71mr105533cwc;
Fri, 17 Sep 2004 04:30:58 -0700 (PDT)

Return-Path:

Received: from gmail.com (200.146.82.91.adsl.gvt.net.br
[200.146.82.91])
by mx.gmail.com with SMTP id o71si30858cwc;
Fri, 17 Sep 2004 04:30:58 -0700 (PDT)
Received-SPF: fail (gmail.com: domain of do_not_rep...@gmail.com does
not designate 200.146.82.91 as permitted sender)

From: "GMAIL ADVERTISEMENTS"

To: xxxxxx...@gmail.com
Subject: GMAIL WEBSITES

  ¶ 9:12 AM