S. 40(a)(ia): Amounts not deductible – Deduction at source -Interest- Where recipient/deductee had already paid tax on impugned amount of interest under section 194A received from assessee by filing return of income, such interest payment could not be disallowed – Second Proviso to section 40(a)(ia) has retrospective effect from 1-4-2005 [ S.194A , 195(3) . 201(1) ]