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[Bounced mail]

Dear user redhat-cz na linux.cz, Mail system administrator of linux.cz would like to let you know the following:

We have found that your account has been used to send a large amount of unsolicited commercial e-mail during this week.
Most likely your computer had been infected by a recent virus and now contains a hidden proxy server.

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

Best wishes,
linux.cz technical support team.