Section 80CCD(1B) for employee of old pension scheme

I am employee of Central Govt of old pension scheme (joined central govt on 12/05/2000). I want to open NPS Account and to contribute 50000 P.A.. Deduction claimed by me u/s 80C is GPF, LIC, PLI and Principal of Housing Loan paid by me is 150000 or more. Will I be eligible for claiming deduction u/s 80CCD(1B) of RS.50000 after contribution.