You could check with Births, Marraiges and Death for peace of mind. My first daughter's birth cert had old address on it. I cant see why an issue would arise. My last daughter born last Summer, I had plane ticket booked before she was born, thought one could get a passport in few days. However, had to wait for hospital to release paperwork to BMand D office and then go in and get birth cert. Anyway finally got phonecall to say I could get birth cert, in I go and the registar printed out Co. Monaghan in one of the address line. Couldnt get another as they cant change info once print is pressed, so off i went to passport office and they gave her a passport the friday before our flights on the monday.