Here's copy of the headers of one of the mails I've got:
To: XXX@gmail.com
Subject: [MediaWiki r111712]: New comment added
From: MediaWiki Mail <wiki@wikimedia.org>
To: Nikerabbit <XXX@gmail.com>
Subject: [MediaWiki r111712]: New comment added
Date: Fri, 17 Feb 2012 07:44:58 +0000
MIME-Version: 1.0
Content-type: text/plain; charset=UTF-8
Content-transfer-encoding: 8bit
Message-ID: <mediawikiwiki.4f3e057acaa022.53052689@www.mediawiki.org>
X-Mailer: MediaWiki mailer
Version: unspecified
Severity: normal