GMX Header Format

Content-Type: text/plain; charset="us-ascii"
Date: Sun, 29 Jul 2007 13:08:52 +0200
From: Username <username@sendinghost.com>
Message-ID: <20070729110852.111111@gmx.net>
MIME-Version: 1.0
Subject: header test
To: Username <username@receivinghost.com>
X-Authenticated: #33333333
X-Mailer: WWW-Mail 6100 (Global Message Exchange)
X-Priority: 3
X-Provags-ID: G11D2DsdDDkF13DrwAc8wFFGyftuH1D+5jsXgvVepqK7XQlVHKHiu
 SekD1HHRJ3gH+9uX8afy+MN4KLoamn6RTgjE== 
Content-Transfer-Encoding: 7bit

Message-ID format:

[UTC-date].[login count]@[host]

- [login count] it looks like this field is count of logins on gmx.net for all users. Till next login this part will be constant.

X-Authenticated: describe personal user id.
X-Provags-ID is unknown.