Salary - Arrears Tax Calculation -Big Problem

Hi.........

This is pankaj.

I have a problem.

If ABC ( Govt. Dept) is employer of  XYZ .As per 6th pay comm., State Govt has declared arrears for 4 years of Rs 100000/- in F Y 09-10. But in F Y 09-10 State Govt has transferred only 20% of total amt , means Rs 20000/- to GPF A/c of the Mr XYZ. &  other remaining amount will be transferred to GPF A/c as following  :

         In F Y 10-11   Rs 20000/- , F Y 11 -12 Rs 60000/-

So, in the above case , Which arrears amount should consider for tax calculation in  F Y 09-10? Rs 20000/- or 100000/-

Please anyone explain me...............

Thanks