Australian subsidiaries of the New York broker, MF Global, entered voluntary administration yesterday. Deloitte announced that it had been appointed administrator of MF Global Australia Ltd, MF Global Securities Australia Ltd and BrokerOne Pty Ltd.The parent company filed for bankruptcy on Monday night. It is reported to have run into trouble as a result of heavy losses sustained as a result of its exposure to European sovereign debt.The Financial Times reported that the group's collapse is the biggest failure of a US financial company since Lehman Brothers in 2008. The paper cited "several people close to last-minute talks" who raised questions about whether MF Global's commodities book was fully funded, which hints at a possible fraud.The New York Times reported that CME Group, which runs the Chicago Mutual Exchange, is investigating reports that MF Global failed to keep customer money separate from company money, as it is required to do.MF Global's Australian activities included trading in equities, futures and contracts for difference. It provided CFD products to a number of local brokers, including CommSec, Westpac Online Broking and ANZ's online broker business, E*Trade.The Australian Securities Exchange advised the administrator that all MF Global companies' participation in ASX markets, as well as clearing and settlement facilities, has been suspended.Deloitte partner Chris Campbell said in a statement: "We have taken control of the assets of the three companies and begun the task of assessing the positions of each, including their over-the-counter derivative positions, such as CFDs."We are commencing a process to reconcile all client positions as at the date of the appointment to determine monies owed to each client. "This will include the necessary close-out of most, if not all client positions in the books of the companies."The Australian Securities and Investments Commission advised clients of other firms trading with MF Global to contact their brokers directly.The Australian Financial Review carried a report yesterday that several Australian banks with exposure to MF Global, through syndicated loans and company bonds, had been dumping their holdings at deeply discounted prices in the secondary market in recent days.The newspaper reported that those with exposures included ANZ, Westpac and National Australia Bank. ANZ is reported to have sold A$25 million of securities at a 30 per cent discount.Reuters reported that trading in Australian grain futures and options was suspended on the ASX futures platform. It said MF Global was a key player in the Australian agricultural futures market.