[ILUG] Clamav How to Schedule scans help

[Frank Murphy]

Having checked
http://www.google.com/search?q=site:www.linux.ie%20clamav

http://www.google.com/search?hl=en&lr=&ie=UTF-8&q=clamav+schedule+scan&btnG=Search

with no sucess,

How do I schedule clamav to scan the box (hda, hdb)

twice a day say, 11am & 11pm,

I know its a  cronjob, that as far as I get.

Have used the webmin module to set up daily updates,
but it doesn't seem to do daily scans.

Frank