1. . Whether the proviso to Sec. 43B of the Income-tax Act, 1961 (hereinafter called the "Act"), inserted by the Finance Act, 1987, with effect from April 1, 1988, shall apply to an assessment proceeding in respect of the assessment year 1984-85 is the question involved in this application.

2. The fact of the matter lies in a very narrow compass.

3. The petitioner is a partnership firm and is an assessee under the Act as a registered firm. The petitioner maintains its accounts under the accounting system which is commonly known as the mercantile system of accounting and its accounting year is from January to December. For the accounting year January to December, 1983, the petitioner filed a return under the Act on August 30, 1984. In its return, it showed a net taxable income of Rs. 4,30,970.

4. In pursuance of a notice issued by respondent No. 3, the petitioner produced its books of account. Respondent No. 3 found that the statutory dues payable during the accounting year on account of Bihar sales tax, additional sales tax, Central sales tax, provident fund and family pension amounting to Rs. 21,15,885 had not been paid by the petitioner; this amount was added to the net i