How do I disable an imobiliser in a renault megane 1.6 S reg?

can anyone please tell me if it is possible and how to disable the imobiliser in a renault megane 1.6 S reg. Garage is stating that it cannot be done and 1st diagnosed the fault as a coil powering up the sparkplugs. after altering the coild they are now stating it is the imobiliser and the car is Kapput. I think theeeere must be away to make the imobiliser release