MF Global missing cash estimates of $1.2 billion are so yesterday.  On Friday, MF Global trustee James Giddens, who oversees the bankruptcy of the U.S. broker-dealer unit, said the estimated gap between potential customer claims and the assets under his control has reached $1.6 billion. The new estimate stem from claims he received from customers who traded on U.S. and foreign exchanges, with about $700 million still in dispute with the British administrators of MF Global UK Ltd.  It was not immediately clear how this affected Giddens' previous estimate of $1.2 billion in missing U.S. customer funds, and a spokesperson for the trustee was not available for comment.  In his emailed statement, the trustee said he had so far returned about $3.9 billion in commodity customer funds, and that about 91% of outstanding claims were for less than $100,000. Giddens also said he's eager "to make additional distributions to former MF Global Inc customers as soon as possible."  However, he's "required by law to hold an appropriate reserve of funds until disputed claims are resolved either through negotiation or by the Court.  At this time, the Trustee anticipates significant disputed claims against the MF Global Inc estate by MF Global Holdings Ltd, MF Global UK Limited, and other entities." The trustee reports that he currently has around $1.4 billion in assets under his control, which he is keeping in reserve. For further details:   [Reuters, 2/10/12].