O'Brien is scheduled to appear before lawmakers with Christine Serwinski and Laurie Ferber, two other MF Global executives named by Corzine as being involved in the transaction, according to the memo. Henri Steenkamp, the firm's chief financial officer, is also scheduled to testify, as is a representative from JPMorgan who has not yet been identified. European Bet MF Global and its brokerage sought Chapter 11 bankruptcy after a $6.3 billion bet on the bonds of some of Europe's most indebted nations prompted regulator concerns and a credit rating downgrade. Corzine quit MF Global Nov. 4. During his testimony, Corzine identified O'Brien as someone with knowledge of a transfer of funds from customer accounts before the firm sought bankruptcy protection Oct. 31. Reid H. Weingarten, O'Brien's lawyer, did not respond to a phone call and e-mail seeking comment.