Service tax refund on sez

Hi All,

Recently my company raised an invoice to a company which is located at speacial economic zone. The invoice includes service tax @ 14.50%.

Now i got a call from the company that they are not going to pay service tax because they are located speacial economic zone and  the will provide me the A1 & A2 form.

Since i made the service tax liability payment towards the specific invoice, now what would be the process to claim the service amount from Service tax Department.

Thanks 

Shib