The confusion arose because the rally organisers initially said the race would be run under the old rules - and only announced the switch after entries had been accepted.
The Dubliner played for England in the 2007 World Cup and under International Cricket Council rules he should be unable to switch allegiance back to the country of his birth until April 2011.
Before making the switch, PricewaterhouseCoopers encouraged its employees to follow some basic rules of etiquette, reminding them, for instance, not to leave uneaten food in someone else's office and urging them to replace office supplies they used.