Pro install fails on ubuntu 8.04 at virtualmin-base postconfiguration

Installing under vanilla minimal Ubuntu 8.04, virtualmin install fails with the following error...

Enabling status monitoring
Error: An error was detected in the new Cron configuration : 0,5,10,15,20,25,30,35,40,45,50,55 * * * * /etc/webmin/status/monitor.pl

Error
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An error was detected in the new Cron configuration : 0,5,10,15,20,25,30,35,40,45,50,55 * * * * /etc/webmin/status/monitor.pl

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dpkg: error processing virtualmin-base (--configure):

Full log attached