Its because the big players need cash to cover some losses elsewhere ( heard there were some lossed in subprime mortgages or something ). So they put their blackboxes on pause until they can free some money to turn them back on. Exchanges prolly demand more margin from institutional players too because they dont trust the banks anymore. Other markets tradet by banks show similar simphtoms. Someone have a daily chart of FGBL for last 3 years with volume?