Made some further improvements:

Altered install so backup only occurs with registered admin for security.
Re-coded so if a old backup less than maximum age does`nt exist, last backup is kept.
IE with 'Backup Save Interval' set to 12Hrs a archived backup is created every 12Hrs.

The settings occur in Module Options, if you can`t set these on your site, install Total Configuration http://addons.oscommerce.com/info/5040 , its a quick, easy install.

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