Notwithstanding anything contained in the Indian Partnership Act, 1932 (Central Act 9 of 1932), or any contract to the contrary, where any firm is liable to pay tax under this Act, the firm and each of the partners of the Firm shall be jointly and severally liable for such payment and accordingly any notice or order under this Act may be served on any person who was a partner during the relevant time, whether or not the firm has been dissolved and all the provisions of this Act shall apply accordingly:
Provided that, where any such partner retires from the firm, he shall be liable to pay the tax, penalty, sum forfeited and interest remaining unpaid at the time of his retirement and any such amount due upto the date of retirement though un-assessed at that date.