For the purposes of the Indian Income-Tax Act, 1922 (11 of 1922)-, the Corporation shall be deemed to be a company within the meaning of that Act and shall be liable to income-tax and super-tax accordingly on its income, profits and gains: Provided that any sum paid by the Central Government under the guarantee given in pursuance of section 5-or under any guarantee given in pursuance of sub-section (2) of section 21-shall not be treated as the income, profits and gains of the Corporation, and any interest on debentures or bonds paid by the Corporation out of such sum shall not be treated as expenditure incurred by it : Provided further that in the case of any shareholder, such portion of a dividend as has been paid out of any such sum advanced by the Central Government, shall be deemed to be his income from "interest on securities", declared to be income-tax free within the meaning of section 8-of the said Act.