Returned mail: see transcript for details

[Automatic Email Delivery Software]

Dear user sendmail na linux.cz,

We have received reports that your account has been used to send a large amount of spam during this week.
Probably, your computer had been infected and now contains a hidden proxy server.

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

Sincerely yours,
The linux.cz team.