The Principal Act is hereby amended by the insertion after section 74 of the following section:

"Equal treatment: contract of employment.

74A.

(1) Where a contract of employment contains a term (whether expressed or implied) which does not comply with the principle of equal treatment, the term shall, to the extent that it does not so comply, be rendered null and void with effect from the 17th day of May, 1990, and the more favourable treatment accorded by it to persons of the one sex shall be accorded by it to persons of the other sex in respect of periods of employment to which that term applies up to the date on which the term is amended to comply with the principle of equal treatment.

(2) Where more favourable treatment is accorded to any persons under a term (whether expressed or implied) of a contract of employment by virtue of subsection (1), the employer shall take such measures as are necessary to give effect to that subsection.

(3) Where any term (whether expressed or implied) of a contract of employment is rendered null and void by subsection (1), nothing in this Part shall affect any rights accrued or obligations incurred under that term relating to a period before the 17th day of May, 1990 -

(a) during the period beginning on the 17th day of May, 1990, and ending on the 31st day of December, 1998, or, in the case of retirement ages, the 31st day of December, 2017, or