I don't know about mobile phones in particular, but if those couriers are objecting to electronic items in general, you can try sending it as a Registered Parcel through the Post Office.
I recently had a graphics card sent to me from Chennai by Registered Parcel. Expect it to be a good deal slower than couriers, including the P.O.'s own courier service Speed Post. But if it's the only way ..... Hope this helps.