Why not... any Somali can live in Somalia irrespective of creed (or lack of). The future Somali State will be citizenship based. The only relevant criteria for extending citizenship status is whether someone was born in Somalia or has somali parents.
Those of you who say no are really advocating for religious apartheid-one law for Somali Muslims and an entirely separate law for non-Muslim Somalis. This will not only fail to endear Somalia to the rest of World but also result in sanctions on Somalia. The world rejected Apartheid South Africa, what makes you think they'll accept Apartheid Somalia?
As long as non-Muslim Somalis are law-abiding citizens, I'll be happy to have them as my neighbours.
Well actually, religious minorites are allowed to have their own religious laws and they don't have to be obligated by Islamic law, its their choice ultimately.
At the end of day, it's not like you entering Mecca or Medina, you don't have to say a shahada to go into Somalia, so if your an atheist you keep it to yourself.