cron error about MySQL

[concept21]

Hi,
My system is Ubuntu 10.04 64 bit.

This cron error message is generated everyday. I can't found any related solution to it by search engine.

Anybody has idea to correct it? It is not a fatal error but annoying.





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Subject Cron <root@localhost> test -x /usr/sbin/anacron || ( cd / && run-parts --report /etc/cron.daily )
Message contents

/etc/cron.daily/logrotate:
/usr/bin/mysqladmin: refresh failed; error: 'Unknown error'
error: error running shared postrotate script for '/var/log/mysql.log /var/log/mysql/mysql.log
/var/log/mysql/mysql-slow.log '
run-parts: /etc/cron.daily/logrotate exited with return code 1