I dont think that anything really needs to be done to the hockey socks being used, but as someone said, skate socks such as the Bauer Elite socks or the Tactics socks, which have kevlar from the ankle bone on up, would certainly prevent these kinds of incidents.
I dont know why more dont wear them, they are normal and nice socks down around the foot and in the skate, and the kevlar material then starts from about the ankle bone up to the knee and protects the entire calf and achilles area.
I push them to as many parents as will listen as I've seen more than a few skaters here at the rink suffer such injuries. A normal cut is bad enough, but when the achilles is involved it can be very serious.
When the Elite first came out, I took a normal core skate sock and the Elite and took a knife to them. It required hardly any pressure from the very sharp knife to slice open the normal sock, but even with very hard pressure, I could not get it to cut the Elite sock and the knife was much sharper than any skate would be. It left a mark, but didnt penetrate. I was pretty impressed.