4.—For the purposes of this Act—

(a) an offence under the law of the sentencing country corresponds to an offence under the law of the State where the act or omission constituting the offence under the law of the sentencing country would, if committed in the State, constitute an offence under the law of the State, and

(b) an offence under the law of the State corresponds to an offence under the law of the sentencing country where the act or omission constituting the offence under the law of the State would, if committed in the sentencing country, constitute an offence under the law of the sentencing country.