Hmm ...
I posted something on the old PsyWar thread about gaining 9th level powers.
And the PsyWar gets 2 more feats (with the Mantled Warrior) than the Psion.
So I put 2+pseudonatural2 together and got, well I didn't get get it.
Still, a lock build with 9th level powers (or spells) would be interesting.
Alas, I'm only good at the psionics side.