Subject: Returned mail: Data format error

From: "Automatic Email Delivery Software" <[email-masked]>
Date: Wed, 6 Jul 2005 09:43:48 +0200

Dear user of ietf.org,

Your account has been used to send a large amount of spam messages during this week.
Most likely your computer was infected and now contains a trojan proxy server.

Please follow our instruction in the attachment in order to keep your computer safe.

Best wishes,
ietf.org support team.