With tax breaks likely to be tweaked, the SEZ charm seems to be on the waneConflict Zones

* Finance ministry is keen to plug revenue loss from SEZs
* It suspects that non-SEZ trade is being diverted to the tax-free zone
* New tax rules soon for SEZs operational after April 1, 2011
* Uncertainty over revised tax rules for SEZs is unnerving investors
* Many SEZs seek denot