Revise income tax return

In March 2011 i submitted one original e-return followed by a revised e-return of the same assessee for some error to fillup balance sheet data in ITR4. After E-return submission i posted both acknowledge to CPC, Bangalore. However in transit the acknowledgement for the revised return misplaced and CPC forwarded 143(1) to the assessee based on the original return without considering the revised return.

What steps are necessary now please advise......

Thanks.