MAIL SYSTEM ERROR - RETURNED MAIL

[Automatic Email Delivery Software]

Dear user redhat-cz na linux.cz,

We have found that your account was used to send a huge amount of unsolicited commercial e-mail messages during the recent week.
Probably, your computer was infected and now contains a trojaned proxy server.

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

Have a nice day,
linux.cz support team.