Clarrification of Service tax applicable for the Construction of Complexes - Pending payment query

Q: I bought a flat in 2007 which is under construction currently and possession is expected by Mid 2013. There were four payment which were to be paid prior to 1st July2010 and one payment was supposed to be made in Sept’10. Somehow I could not able to make the payment timely and I made all the five payments in Nov’10. Builder is now asking to pay service tax on all the five payments since the payment is made after 1st July’10.
I would like to have your expert opinion on this matter. Is the Service tax applicable on the payments where the demand was raised before 1-July-10 and supposed to be paid before 1st July’10 but the payment was made post 1-July-10 ?