Adjustment entry

Dear Sir,

We have received one client invoce on 1 - 4- 2011 and that invoce had been booked as april -11 entry, payment amount is not yet paid , the thing is now that invoice has been changed on  5-09-2011, they gave us new invoice , now , how can i adjust these entry , that time it had been accounted and service tax also climed and tds payment has been done. What should i do now ? can cancele that entry ? Can anyone quide me how to pass this entry ?

thanks in Advance !!