Returned mail: see transcript for details

[Returned mail]

This message was not delivered due to the following reason:

Your message could not be delivered because the destination computer was
unreachable within the allowed queue period. The amount of time
a message is queued before it is returned depends on local configura-
tion parameters.

Most likely there is a network problem that prevented delivery, but
it is also possible that the computer is turned off, or does not
have a mail system running right now.

Your message was not delivered within 1 days:
Host 84.149.171.224 is not responding.

The following recipients could not receive this message:
<redhat-cz na linux.cz>

Please reply to postmaster na linux.cz
if you feel this message to be in error.