THE Margin's "omens of things" to come department is interested to note that TSB and Ulster Bank will today sign an ATM sharing agreement. Ulster, of course, is still interested in buying TSB, but readers will remember that the trustees favoured the other main bidder - National Australia Bank. So are relations warming between the TSB and Ulster? The Margin doubts it. In any case, the TSB is unlikely to be on the market for some time yet with the Labour Party contriving to turn the third banking farce into a long-running epic.