Service tax after getting Completion Certificate

Can anyone help me out in this disputed case:

A Real estate company gets its project completed on 01-10-10 (i.e after receiving the Completion Certificate from municipality).I have a customer from whom i have to receive an amount of Rs.20kahs(the flat was booked before 01-07-2010 i.e applicablity date) which he pays after 01-10-10.My Question is will he be liable to pay service tax on this amount of Rs.20l which he pays after 01-10-10.