All PS3s are backward compatible with PS2 software.

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the2real4mafol said:
It's a shame you have to hack your machine to do this, it's like a choice between PS2 games and PSN, it's hard to say which to choose when you already have a PS2 anyway.

You can still go on PSN with a hacked console, things have moved a long way since only 3.55 firmware being available.