serf - the timeline is important to have accurately.
Raymond James was one of the earliest brokers to suspending trading (I don't recall if it suspended just buys, or both buys and sells).
Ameritrade started hanky panky early - Aug 28 allowed only sales, I think. Aug 29 stopped both sales and buys
Scottrade, while denying to a client they would do so, the previous trading day, nonetheless broke their word and stopped trading the next day, which was an entire day before the official halt.
These brokers, alone, manipulated the price downward significantly in just 3 days before the official suspension on Auyg 31, 05.
After the suspension was lifted,on 9/15, Ameritrade allowed a few trades for about an hour, then halted. Scottrade continued to deny trades. A canadian broker was the last trade on 9/16 at very depressed price of .004 (although it was listed as .005).