Can I club two LTA entitlements and avail tax benefits for both in a block of 4 years,i.e. if my annual LTA amount is Rs.10,000, can I avail Rs.20,000 deduction, by clubing two years, say 2006 & 2007,in C.Y.2007 and again for two years,2008 & 2009, in C.Y.2009, within the block of 4 years.