Stipulations on 8k homebuyers tax credit?

My fianc� and I bought a house in September 2009 and received the 8k tax credit. Both of our names are on the deed of the house, however only his name is on the loan because he had better credit at the time. Well we are now in the process of splitting up. He has agreed to move out, but remain co-owners of the house, and allow me to pay him the cost of the mortgage every month. However, I'm not sure exactly what the stipulations are for the tax credit. If he moves out before September 2012 will he have to re-pay the 8k even if I continue to live in the house?