The Irish financial community has never been huge, but last week's $750m foreign exchange disaster has underlined what a tiny world it is. Pat Ryan, group treasurer at Allied Irish Banks, has been sent out to sort the mess at Allfirst in the US. He worked on the same dealing desk at the Irish central bank as Dave Cronin, one of the staff suspended at Allfirst last week.

But even closer ties exist elsewhere. Maurice Crowley, the former head of investors relations at AIB, is now the chief financial officer of Allfirst.