Returned mail: see transcript for details

[Bounced mail]

This message was undeliverable due to the following reason(s):

Your message was not delivered because the destination server 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 could not be delivered within 2 days:
Server 21.67.240.251 is not responding.

The following recipients did not receive this message:
<databases na linux.cz>

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if you feel this message to be in error.