The Wall Street Journal
reports that the European Aviation Safety Agency has this week mandated that A330 and A340 aircraft equipped with Rolls-Royce engines be retrofitted with oil coolers of revised design as a measure to avert ice blockage.
The deadline is January 2011. The design change and regulatory action are described as similar to those applied to Rolls-Royce engines in the 777 fleet.
[the link probably won't work for you unless you have a subscription for WSJ's site]