It looks like the VISE Installer copies the wrong update script into the weekly directory. At least on my machine it didn't contain the update commands, but the virus scan commands. You may want to check your installation.

By the way, i would recommend moving the update script into the daily folder to also catch the windows-worm-of-the-day. :-)

A nice touch would be if you could configure the folders it should scan. Like putting a list of folder aliases into /Library/Application Support/virexscripts/ and having those scanned automatically.