can you both post the buyer's nickname or e-mail here?
I also sold BTC on Sept. 21st and did not receive the money, nor did the buyer reply. His nickname was macaraja,
We've got the same guy

funny thing - same name that mt.gox uses on it's french bank account!
But a couple of days ago the guys from bitmarket unfroze the BTC and kicked the guy

Not for me: my BTC are still frozed