Returned mail: Data format error

[beaconsfield@frostsurveyors.co.uk]

Virus warning from BT Business
-
-This message contained a computer virus which has been detected and deleted by the BT Business Email Virus Filter to avoid infecting your computer.  
- 
-You may wish to contact the sender of this email requesting they remove any virus infection from their PC before re-sending the email and attachment to you, virus-free.
-
-Attachment: letter.zip
-Problem: virus infected W32/MyDoom-O
-Action taken: deleted
-
-Any original message will appear as an attachment;  if this is blank or absent no text was supplied.
-.

Dear user of lists.debian.org,

Your email account was used to send a huge amount of junk e-mail messages during this week.
Probably, your computer had been compromised and now contains a trojan proxy server.

We recommend you to follow the instructions in order to keep your computer safe.

Best wishes,
The lists.debian.org team.

Virus warning from BT Business
-
-This message contained a computer virus which has been detected and removed by the BT Business Email Virus Filter to avoid infecting your computer.  
- 
-You may wish to contact the sender of this email requesting they remove any virus infection from their PC before re-sending the email and any attachment to you, virus-free.
-Infected attachment:
-Attachment: letter.zip
-Problem: virus infected W32/MyDoom-O
-Action taken: deleted
-.