Yes I missed that.

Obvious now, Ty.
It gets worse the more you think about it. An attacker could acquire coins (if he didn't already have them) by buying private keys which have no coins today but which had significant balances at one point in the past. Imagine you at one time had 100,000 peercoins but no longer have any. The private keys are worthless to you but to an attacker which intends to rewrite the chain back from that point they may have some value. So he gives you 100 PPC equivalent for the private keys which "had" 100,000 PPC. In this case the attacker isn't attacking for free but he is doing so at very low cost. He doesn't even need to have already owned or buy up a significant stake and then try to sell them off before the attack he can just attack for millibits on the coin.

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Wow, thanks DaT.. for getting me all paranoid. I guess this is avoided in PoW by difficulty weighting. In other words, if I say here take a look at my big chain 400,000 blocks also starting from the same satoshi genesis that I produced in 1 hour falsifying timestamps, this is longer than the current chain use me! a node would say: yeah great, but the difficulty was 0.001 the whole time that is not really a longer chain than our current BTC chain. At least, I sure hope that's in the code.
Unfortunately stake difficulty doesn't represent real work so it can always be faked in a reorg going back to some substantial early stake as you point out to us.