Well the answer that works for mostly all the country's is that it's not a legal currency, and very few countries have accepted it, and many countries do not really like it. Now why they don't like it, cause you can't track the owner of Bitcoins, there is no reverse payment, one can technically disappear with his coins and no one will even know where he went. No offence to your country but major scams are reported from Nigeria, and if it were to be allowed it could increase as it leaves no paper trail. So that's the simple reason why it's not keen,according to me that's the scene.