[squid-users] blocking malware by useragent?

Yes, it's me again... sorry for bothering with "useragent" issues these
days, but I'm reading and finding out stuff (on the 'net and in our LAN)
that I'd like to share with you all.
So, here I'm back again, asking whether anybody knows of some useful and
working "Malware useragent blocking list". I got inspiration from here:

http://www.bleedingsnort.com/cgi-bin/viewcvs.cgi/sigs/MALWARE/MALWARE_USER_Agents?rev=1.7

Any thoughts/opinions/success stories about this?

Thanks again,

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Boniforti Flavio
Provincia del Verbano-Cusio-Ossola
Ufficio Informatica
Tecnoparco del Lago Maggiore
Via dell'Industria, 25
28924 Verbania
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