The corruption may occur during the download process (you can experience this even when downloading from a site) so a file may not necessarily corrupt at it's source.
In other words, even if you get a corrupt file from a certain source, it doesn't mean that that soure is serving a corrupt file, so to ban automatically all IP adresses that serve corrupt files you would need a pretty amazing "corrupt-file" criteria thingy.

__________________
iMac G4 OSX 10.3.9
RAM 256MB
LW 4.10.5 Basic
ADSL anything from 3 to 8Mbps/around 1024kbps

"Raise your can of Beer on high
And seal your fate forever
Our best years have passed us by
The Golden Age Of Leather"
-Blue Öyster Cult-