Strange transaction (block 71036) What happened to this transaction?

Can someone explain it?

http://blockexplorer.com/t/9eHTFRi3Qq
On July 29 2010, it was discovered that block 71036 contained several transactions with a ton of OP_CHECKSIG commands. There should only ever be one such command. This caused every node to do extra unnecessary work, and it could have been used as a denial-of-service attack. A new version of Bitcoin was quickly released. The new version did not cause a fork on the main network, though it did cause one on the test network (where someone had played around with the attack more).


https://en.bitcoin.it/wiki/Incidents#OP_CHECKSIG_abuse