apllicability of service tax to be calculated from

May any one kindly anwser my question please   
I want to Know Service tax for Renting Properties (commerical)  to be calculated from , 01/04/2007 (i.e, from April 2007 to March 2008 ) or from 01/06/2007 ( i.e, june 2007 onwards ) because pro at Service tax office is also ill informed about this,
                                                                                   srigd @ sify.com